Eeschema: fixed bug 577083. Also fixed a bad import of predefined fields when loading a component from a library, when this component has some empty fields like footprint and documentation but have user fields not void.

Eeschema: fixed bug 577083. Also fixed a bad import of predefined fields when loading a component from a library, when this component has some empty fields like footprint and documentation but have user fields not void.

Minor fixes. Board and footprint editors: Auto update 3D display after footprint or board edition. Convert gendrill dialog from DialogBlocks to wxFormBuilder

Preparing 3D view autorefresh when editing a footprint in modedit (not yet working)

preparing auto refresh of the 3D view in mod edit (not yet working)

* Closes bug report 570021.
* Removed unused variable from pcbnew.cpp
* Use new message box methods when saving board file.
* Minor code cleaning.

* Removed redundant empty string test, thanks again Alain.
* Minor code cleaning.