corrected display problems in MoveSelectedTool and LivePreviewManager

[codeprof]

• changing ctx.Operator before a call to layer.Draw(...) has no effect because the BlendMode is overwritten by layer.Draw(...).
  The error can be seen e.g. when having a colored semi-transparent image and apply a black and white filter. In the regions of the image where alpha is != 255 there remain colored parts.
• Layerproperties are corretly applied if "MoveSelectionTool" is active, but not if "MoveSelectedTool" is active.
• MoveSelectedTool does not react on changes in Opacity, Visibility and BlendMode

[robpvn]

I no longer feel confident about making decisions on things not not directly related to addins, so @cameronwhite will have to make an opinion here I think. But I can say that there is a problem with indentation caused by tabs vs. spaces here too, which will need correcting. 👌

[codeprof]

Updated intends (by replacing 4 spaces with tab, don't know why mono used spaces...)

[cameronwhite]

Can you remove this line instead of leaving it commented out? Otherwise, the changes look good

[codeprof]

@cameronwhite
Are there still obstacles preventing you from merging this? If so I will try to improve :-)

[cameronwhite]

Looks good - I just didn't see the new commit.

[codeprof]

no problem. Thank you for merging it :-)