This is a bit critical.  I accidently left in some code that replaces 1's with 0's in Paste.  Oops.  Also removes spaces.  So that's fixed.  Also a slew of bugfixes from Franz, some bugfixes in Open Imported Module, paste properly handles selected text, and some other minor bugfixes.

I also added Check Syntax, and the option in prefs to check syntax on save (off by default).

This uses the builtin function compile, then tabnanny, on the current document.  It only checks syntax in the current document (imported files are ignored).