* Do not compile dxf old files.
* import gfx, gal mode: make absolute placement working.
* Import gfx in legacy canvas: use it and make interactive placement working
* Take imported line width in account. Ensure DXF line thickness is OK.
* handling empty files in legacy mode.
Improve dialog layout and fix UI policy issues with all of the dialog
boxes in the Gerbview and Pcbnew code paths.
Updated the use of component to footprint where appropriate.