Add support for Amazon Bucket

Let's do it on next pull request

Rubocop is a Ruby static code analyzer. Out of the box it will enforce many of the guidelines outlined in the community

Add support to Onedrive is important to give the cartup flexibility.

After cartup uploads the artifact some problem when it try to tag the current branch.

bundler: failed to load command: cartup (/usr/local/bin/cartup)
NameError: uninitialized constant GitHelper::CartLogger
/usr/local/lib/ruby/gems/2.4.0/gems/cartup-0.1.7/lib/git_helper.rb:6:in tag_to' /usr/local/lib/ruby/gems/2.4.0/gems/cartup-0.1.7/lib/cartup.rb:29:in run'
/usr/local/lib/ruby/gems/2.4.0/gems/cartup-0.1.7/lib/cartup_command_helper.rb:24:in handle' /usr/local/lib/ruby/gems/2.4.0/gems/cartup-0.1.7/exe/cartup:12:in <top (required)>'
/usr/local/bin/cartup:23:in load' /usr/local/bin/cartup:23:in <top (required)>'

Today the template copied from project comes with the two options google cloud and amazon s3 like:

project:
  framework:
    version: "0.0.1"
    name: "<Name you use to archive the FRAMEWORK on Carthage>"
  google:
    project_id: "<Insert here Google project ID>"
    credentials_file: "Insert here The path to credential file that you download from firebase"
    bucket: '<Insert here the name of destination bucket on google cloud>'
  s3:
    region: "<Insert Region Name where you bucket is located"
    bucket_name: "<The nam of you bucket>"
    bucket_access_key: '<Your access key>'
    bucket_secret_key: '<Your secret key>'

We should add a parameter like: --s3 or --google-storage to inform cartup to only create the template wished. Like

cartup init --s3

output:

project:
  framework:
    version: "0.0.1"
    name: "<Name you use to archive the FRAMEWORK on Carthage>"
  s3:
    region: "<Insert Region Name where you bucket is located"
    bucket_name: "<The nam of you bucket>"
    bucket_access_key: '<Your access key>'
    bucket_secret_key: '<Your secret key>'

Add support to dropbox is important to give the user of cartup flexibility.