Revert "Revert "Update README.md""

This reverts commit 682f8ac89bd4c73787defabbed6231ce930aea24.
Revert "Revert "add coverall""

This reverts commit 0dc0535f81bb0aec014984f8f3799a0fe7acbdac.

Conflicts:
	spec/spec_helper.rb
Revert "Revert "add service name for coverall""

This reverts commit c6a7920e884ec96c2d803d136878ac2f92ebf83f.
change coveralls repo token
move coveralls to gemspec