adds method to githubdataloader module to return all commits from a repo by author
adds method for returning commit number on a repo for a contributor. Removes unuseful code returning all commits
adds spec for githubdataloader return_author_commit_number method and removes old spec
method to return a repo's number of watchers
test back in
Merge pull request #59 from dmill/github_statistics

Github statistics
deals with merge conflicts