small fixes to display-mode=usage

git-svn-id: http://haxe.googlecode.com/svn/trunk@6621 f16182fa-f095-11de-8f43-4547254af6c6
another attempt at better legacy switch error reporting (fixed issue #1720)

git-svn-id: http://haxe.googlecode.com/svn/trunk@6622 f16182fa-f095-11de-8f43-4547254af6c6
CHANGES.txt update

git-svn-id: http://haxe.googlecode.com/svn/trunk@6623 f16182fa-f095-11de-8f43-4547254af6c6