Patch from ch3cooli:
Do not open change encoding dialog if that view is readonly

git-svn-id: http://tortoisesvn.googlecode.com/svn/trunk/src/TortoiseMerge@24245 4cfb86a4-2c7a-11df-bd14-c1e331e6ceac
Set the view as modified if lines are copied, even empty ones.

git-svn-id: http://tortoisesvn.googlecode.com/svn/trunk/src/TortoiseMerge@24246 4cfb86a4-2c7a-11df-bd14-c1e331e6ceac