key handler: moving normalizeCommandKeys to ace/lib/keys

Conflicts:
	lib/ace/lib/event.js
extracting sendKeys from vim_tests and adding it to ace/lib/keys (keys.send)
using keys.send in emacs tests
adding keys.simulateKey that can be used to inject command and string
insertions into editor
e.g.
keys.simulateKey(editor, 'Right')
keys.simulateKey(editor, 'a')
keys.simulateKey(editor, 'Command-a')
etc
vim test: removing old code
fix key simulation with jsdom