auto-indentation of pasted text now only happens when complete
lines including a trailing paragraph separator are copied and pasted.
In addition, the reindent() functions ensures that the relative indentation
within the pasted block is preserved. This mechanism is now also used for
moving lines up/down.
Done with thorbjorn
actual whitespace when the indentation column changes.
Complete whitespace cleanup can still be done either automatically
on save (when configured) or when explicitely called with the
"Clean Whitespace" action from Edit/Advanced.
- when doing backspace, preserve the previous indentation litterally
- when having auto-indentation turned off, simply repeat the previous
indentation litterally instead of jumping to 0
