Issue was caused by some stuff happenign in wm_operator_finish() which uses
to somehow restore changes made by transformation invoke function.
Solved by not calling translation operator directly from duplication operator
(which is in fact really tricky) and use macros instead. This macros calls
duplication operator which simply duplicates strip, and then calls translation
operator.
Separated preview drawing into own ARegion, this should make using View2D possible
The Sequencer now has three view types: Sequencer, Preview and split Sequencer/Preview.
Changing the preview can be done either by the combobox in the header or toggling through those types with CTRL+TAB.
Notes:
* Icon for split Sequencer/Preview view missing still.
* Naming items in the comboboxes can be improved (just Preview instead of Image Preview?)
Next steps:
* bringing back View2D handling (zoom/pan) for image preview
* experimenting with splitting the Preview ARegion for In/Out editing
GPencil code back!
Joshua will probably take this further. I've added XXX notes
where fixes are required. Also note that ED_gpencil.h has
all old exports, which is probably not needed, most can go
to gpencil_intern.h
Also added Makefile fixes for sculpt