Refactoring #1488

Updated by pospelov over 3 years ago

This is a heavy item which requires the following

* -Embed Embed mask editor into ImportDataView- ImportDataView
* Make FitSuite respecting masks and ROI
* -Create Create a widget which will allow to link real data with certain instrument- instrument

And some small improvemente
* provide right-mouse button context menu for tree selector
* take care of splitter's initial left-right-width (now it appears differently on different monitors)