Log message

Tried to fine-tune the auto-completion behaviour esp. for automatically inserted
suggestions and increased the minimum auto-complete delay to 0.5s since below
that a fight between computer speed and user typing speed could occur.
This addresses i625.

	Modify	/trunk/Interfaces/English.lproj/Preferences.xib	diff
	Modify	/trunk/Source/CMTextView.m	diff
	Modify	/trunk/Source/SPNarrowDownCompletion.h	diff
	Modify	/trunk/Source/SPNarrowDownCompletion.m	diff