swift234

Reserve "non-literal" use of various characters for now

Given that we want semicolon statement separators to be optional,
literals can bump up right next to the previous statement at the moment:
'var x = y"hello".print()' is two statements right now, not one broken
expression being used to initialize to 'x'.  This is unfortunate if we
ever want to support C++ style raw strings or otherwise have some back
pocket grammar tricks to implement type state or trivially unambiguous
generics.

Swift SVN r3871