Update project settings for swift.
Rewrite AppDelegate with Swift.
Rewrite Common.h into Constants.swift
Rewrite AllkdicController into AllkdicManager.
Rename AllkdicContentView to AllkdicContentView.
Replace name `menu` with `mainMenu`.
Rewrite ContentViewController
Rewrite PreferenceWindowController
Add `Label` control.
Rewrite AboutWindowController in Swift.
Remove Common.h
Rewrite KeyBinding with Swift.
Replace `import Cocoa` with import `import AppKit`
Remove `NSWindow+CamBecomeKeyWindow`
Change file order in Xcode.
Merge pull request #12 from devxoul/swift

Rewrite into Swift.