New streams added by @adamwtow required camera info topics to be published

librealsense allows a number of camera parameters to be set. These should be made available to the use of the wrapper.

Note: #4 will likely be implemented first, allowing preset camera combinations to be used

librealsense provides the means for change a number of camera parameters (exposure setting etc) and have set up some preset combinations. This should be available to users on launching the node. Another issue will be raised to set specific camera parameters.

Provide the necessary install instructions incl. dependencies
Specify what is and isn't currently implemented
Mention development for APC

Significant amount of legacy code. Can probably also remove the need for customPCLconfig.cmake.

Currently the depth images are published in mm for use with PCL Kinect Fusion. This should be made user selectable between m, mm or raw unitless depth.

@adamwtow can you add more information about the bug you mentioned, specifically the order of things you mentioned re: RVIZ. I will try and hunt it down when I get a chance.

Librealsense provides a number of additional streams which currently aren't implemented. These should be included. Special consideration should be taken for the infrared2 stream which is only valid for R200.