File action icons
Add changesForRef:parent:

The API may need to change as more diff stuff is moved to Objective Git.
Change icons in file list
Fix column sizing
Adjust truncation depending on change icon visibility
Change icons for folders
Show deletions
Add -stageAllFiles
Revert to command-line staged/unstaged reading

It's not working, and the Objective Git API is about to change.
Fix XTStageViewController for tests
Update XTFileListDataSourceTest for showing deleted files
Rewrite checkout:error:, add detached head test
XTTextPreviewController
HTML preview for text files
Text preview tweaks
Merge remote-tracking branch 'origin/text'
Clickable parents
Merge branch 'master' into header

Conflicts:
	Xit.xcodeproj/project.pbxproj
	Xit/XTFileViewController.m
	Xit/XTFileViewController.xib
XTWebViewController