Cosmetic enhancements. Eeschema: in libedit the Value Field is n more editable in the field editor dialog (due to recent changes in library code)

minor cleanup. minor enhancements. Finish file housekeeping. add Bug 682586 fix from Mark van Doesburg.

Eeschema: fix bug in load_one_schematic_file.cpp: error about files version, that create errors for hierarchical labels.
Pcbnew: cleaning code in block.cpp, and modifye previous way to calculate block size in block command, because old way creates unexpected behavior in block rotate and block flip.
Pcbnew: Fix a bug in plot silkscreen layers.
Cvpcb: Fix compilation issue under MACOX