[processing] [feature] split lines with lines
Log error to ProcessingLog
Merge pull request #1719 from bstroebl/splitLines

[processing] [feature] split lines with lines
dxf export:
* export layers in reversed rendering order
* use checkboxes for layer selection
* support for layers selection by visibility preset
* improve selection of layer attribute
* show busy cursor while exporting
* fix duplicate end of entities section
indentation update
Enable coverage for Travis builds
Try excluding some files from coverage
Tweak flags