Changed v0.18.0.json so diffWorkDir DiffOptions argument is optional. Added .idea to .gitignore to support webstorm.
Updated v0.18.0.json to make the index and DiffOptions arguments in tree.diffIndex optional (libgit2 supports null for both)
Merge pull request #103 from kciccarello/master

Changed v0.18.0.json so diffWorkDir DiffOptions argument is optional. Ad...