Remove deployment target setting on the target "CotEditor"
Remove DVKQueue and use NSFilePresenter instead

Conflicts:
	CotEditor.xcodeproj/project.pbxproj
Stop using NumberOfSavingFlags property
Use NSFileCoordinator to get file attributes
Compare MD5 hash on presentedItemDidChange

ファイル読み込み時と保存時のDataのMD5ハッシュを保存し、ファイル更新の通知が合った際に比較。
Remove descriptions about DVKQueue from documents
Set document's fileModificationDate again after saving
Merge pull request #38 from 1024jp/fix/issue29_externalUpdateAlert

Fix unwanted external update alert (issue #29)