Backend: PDF documents: Fix export as a PDF (aka copy)

Signed-off-by: Jerome Flesch <jflesch@wyplay.com>
Main window: don't try to display the doc or the page if it's already displayed

Signed-off-by: Jerome Flesch <jflesch@wyplay.com>
Merge branch 'testing' into unstable

Conflicts:
	src/paperwork/frontend/mainwindow.py

Signed-off-by: Jerome Flesch <jflesch@wyplay.com>
Main window: Fix page drag-n-drop inside the page list

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Main window: Fix page->doc drag-n-drop

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Backend: Don't make temporary files to run the OCR, it's not required

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Backend: fix page scan

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Docsearch/cleanup: There is no temporary files for rotated image anymore --> no cleanup to do

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Merge branch 'testing' into unstable