bug fix & change/cleaning in my research code
Fix bug when import button had to be clicked twice if a textbox was changed

If a textbox was changed, and right after that import button was
clicked, then the onClick on button was not being called, jus the
onchange on the input field was occuring. Have fixed that
Fix when a non json file is imported with JSON option
WK-39: Allow PyTransform command to edit the current column
Fixed issues with Edit Python Transform and Undo-Redo of python transformation
v190: better Python Transform WK-39, bug fixes.
Merge branch 'development'