Add configuration class

* Allow configuration of a branch to run coverage on (all is default)
* Allow disable of warnings ("Not reporting to Code Climate...")
Add Ci and Git classes
add logger for warning messages
Add configuration example to readme
Merge pull request #18 from cball/add-config-specify-branch-and-hide-warnings

Add configuration class, ability to specify a branch to run coverage on, and ability to silence warnings
Slim down config section in README

Most users don't need to config, so don't want to emphasize it.
Merge branch 'master' into patch-1

Conflicts:
	lib/code_climate/test_reporter.rb
Use the configuration to store the SimpleCov profile