Merge pull request SwiftGit2#102 from jakeva/develop

Implement git status and diffs

Merge pull request SwiftGit2#82 from SwiftGit2/swift3-readme

Update README.md for Swift 3

Merge pull request SwiftGit2#43 from SwiftGit2/antitypical-result

Switch from LlamaKit to antitypical/Result

Dashes, not emdashes