Attempted a fix for recently-reported qCompleter crashes.
-  lqlw.select_callback and lqlw.tab_callback now use: :
     w = c.k.autoCompleter.w or c.frame.body.wrapper
- Disabled the utterly weird "klass" hack in lqlw.tab_callback.
  According to blame I'm responsible for this, but it's hard to believe...
- Removed definition of getInsertPoint in c.frame.body.
- Changed asserts to calls to g.trace in lqlw.set_position.  Assert have no place in such code.

Leo build: 20140919060946