add support for @:deprecated (fixed issue #1346)

git-svn-id: http://haxe.googlecode.com/svn/trunk@5812 f16182fa-f095-11de-8f43-4547254af6c6
handle null expressions in haxe.macro.ExprTools.toString

git-svn-id: http://haxe.googlecode.com/svn/trunk@5813 f16182fa-f095-11de-8f43-4547254af6c6
Merge branch 'haxe/master'