add linecard metrics (state, uptime, cpu/mem utilization) about junos_exporter HOT 7 CLOSED

<rpc-reply xmlns:junos="http://xml.juniper.net/junos/15.1R7/junos">
    <fpc-information xmlns="http://xml.juniper.net/junos/15.1R7/junos-chassis" junos:style="verbose">
        <fpc>
            <slot>0</slot>
            <state>Online</state>
            <memory-dram-size>1024</memory-dram-size>
            <start-time junos:seconds="1540974142">2018-10-31 08:22:22 UTC</start-time>
            <up-time junos:seconds="18847524">218 days, 3 hours, 25 minutes, 24 seconds</up-time>
        </fpc>
    </fpc-information>
    <cli>
        <banner>{master:0}</banner>
    </cli>
</rpc-reply>

show chassis fpc detail | display xml
<rpc-reply xmlns:junos="http://xml.juniper.net/junos/18.4R1/junos">
    <fpc-information xmlns="http://xml.juniper.net/junos/18.4R1/junos-chassis" junos:style="verbose">
        <fpc>
            <slot>0</slot>
            <state>Online</state>
            <temperature junos:celsius="39">39 degrees C / 102 degrees F</temperature>
            <memory-dram-size>16384</memory-dram-size>
            <memory-sram-size>0</memory-sram-size>
            <memory-sdram-size>0</memory-sdram-size>
            <start-time junos:seconds="1559804691">2019-06-06 07:04:51 UTC</start-time>
            <up-time junos:seconds="16737">4 hours, 38 minutes, 57 seconds</up-time>
        </fpc>
    </fpc-information>
    <cli>
        <banner>{master:0}</banner>
    </cli>
</rpc-reply>

show chassis fpc detail | display xml
<rpc-reply xmlns:junos="http://xml.juniper.net/junos/17.3R3/junos">
    <fpc-information xmlns="http://xml.juniper.net/junos/17.3R3/junos-chassis" junos:style="verbose">
        <fpc>
            <slot>1</slot>
            <state>Online</state>
            <temperature junos:celsius="30">30 degrees C / 86 degrees F</temperature>
            <memory-dram-size>2048</memory-dram-size>
            <memory-rldram-size>1036</memory-rldram-size>
            <memory-ddr-dram-size>11264</memory-ddr-dram-size>
            <start-time junos:seconds="1550101033">2019-02-13 23:37:13 UTC</start-time>
            <up-time junos:seconds="9720385">112 days, 12 hours, 6 minutes, 25 seconds</up-time>
            <max-power-consumption>584</max-power-consumption>
        </fpc>
        <fpc>
            <slot>2</slot>
            <state>Online</state>
            <temperature junos:celsius="30">30 degrees C / 86 degrees F</temperature>
            <memory-dram-size>2048</memory-dram-size>
            <memory-rldram-size>1036</memory-rldram-size>
            <memory-ddr-dram-size>11264</memory-ddr-dram-size>
            <start-time junos:seconds="1550101046">2019-02-13 23:37:26 UTC</start-time>
            <up-time junos:seconds="9720372">112 days, 12 hours, 6 minutes, 12 seconds</up-time>
            <max-power-consumption>584</max-power-consumption>
        </fpc>
        <fpc>
            <slot>9</slot>
            <state>Online</state>
            <temperature junos:celsius="28">43 degrees C / 109 degrees F</temperature>
            <memory-dram-size>3124</memory-dram-size>
            <memory-rldram-size>516</memory-rldram-size>
            <memory-ddr-dram-size>8192</memory-ddr-dram-size>
            <start-time junos:seconds="1550101152">2019-02-13 23:39:12 UTC</start-time>
            <up-time junos:seconds="9720266">112 days, 12 hours, 4 minutes, 26 seconds</up-time>
            <max-power-consumption>465</max-power-consumption>
        </fpc>
        <fpc>
            <slot>10</slot>
            <state>Online</state>
            <temperature junos:celsius="0">44 degrees C / 111 degrees F</temperature>
            <memory-dram-size>3584</memory-dram-size>
            <memory-xr2-size>259</memory-xr2-size>
            <memory-ddr-dram-size>24960</memory-ddr-dram-size>
            <start-time junos:seconds="1550101065">2019-02-13 23:37:45 UTC</start-time>
            <up-time junos:seconds="9720353">112 days, 12 hours, 5 minutes, 53 seconds</up-time>
            <max-power-consumption>496</max-power-consumption>
        </fpc>
    </fpc-information>
    <cli>
        <banner>{master}</banner>
    </cli>
</rpc-reply>

<rpc-reply xmlns:junos="http://xml.juniper.net/junos/17.3R3/junos">
    <fpc-information xmlns="http://xml.juniper.net/junos/17.3R3/junos-chassis" junos:style="verbose">
        <fpc>
            <slot>0</slot>
            <state>Online</state>
            <temperature junos:celsius="38">38 degrees C / 100 degrees F</temperature>
            <memory-dram-size>2048</memory-dram-size>
            <memory-rldram-size>1324</memory-rldram-size>
            <memory-ddr-dram-size>5120</memory-ddr-dram-size>
            <start-time junos:seconds="1540320035">2018-10-23 18:40:35 UTC</start-time>
            <up-time junos:seconds="20179996">233 days, 13 hours, 33 minutes, 16 seconds</up-time>
            <max-power-consumption>440</max-power-consumption>
        </fpc>
        <fpc>
            <slot>1</slot>
            <state>Online</state>
            <temperature junos:celsius="37">37 degrees C / 98 degrees F</temperature>
            <memory-dram-size>2048</memory-dram-size>
            <memory-rldram-size>1324</memory-rldram-size>
            <memory-ddr-dram-size>5120</memory-ddr-dram-size>
            <start-time junos:seconds="1540320036">2018-10-23 18:40:36 UTC</start-time>
            <up-time junos:seconds="20179995">233 days, 13 hours, 33 minutes, 15 seconds</up-time>
            <max-power-consumption>440</max-power-consumption>
        </fpc>
        <fpc>
            <slot>2</slot>
            <state>Online</state>
            <temperature junos:celsius="31">31 degrees C / 87 degrees F</temperature>
            <memory-dram-size>2048</memory-dram-size>
            <memory-rldram-size>662</memory-rldram-size>
            <memory-ddr-dram-size>2560</memory-ddr-dram-size>
            <start-time junos:seconds="1540320034">2018-10-23 18:40:34 UTC</start-time>
            <up-time junos:seconds="20179997">233 days, 13 hours, 33 minutes, 17 seconds</up-time>
            <max-power-consumption>227</max-power-consumption>
        </fpc>
    </fpc-information>
    <cli>
        <banner>{master}</banner>
    </cli>
</rpc-reply>