direct use of undefined changed to void 0
== undefined -> == null; fixes #642
Fixes AIContext >> initializeInterpreter
Merge branch 'upstream' into tamed-undefined
Recompiled amber.
Fixes AIContext >> retrieveNode
Update AIContext >> isBlockSelector comment update
Merge branch 'upstream' into tamed-undefined

Conflicts:
	js/Compiler-Interpreter.js
AIContext refactoring. AIContext is now a subclass of MethodContext
Merge branch 'upstream' into tamed-undefined

Conflicts:
js/Compiler-Interpreter.js
Recompiled Test.js and CLI
Merge pull request #668 from herby/tamed-undefined

Tamed undefined
avoid reflows by using a DocumentFragment
boot.js: do not use finally {} in st.withContext as it slows down considerably events (where there's no outer context)
revert commit ef214a0 as CodeMirror seems to have issues with it.
Merge remote-tracking branch 'upstream/master'