Eeschema: always stores sheet filename in unix-like notation, and fix a  bug when editing sheet file  name.
Pcbnew: add PDF format  for drill map generation.
Plotter classes: tweaking code.

All: remove macros  MAX, MIN, ABS from macros.h and replace these macros by std::max, std::min and std::abs (mainly found in old code).

SVG plotter: fix issues in draw arc and draw rectangle.

Eeschema: Plot dialogs: unify 5 dialogs (which means 5 duplicate code) to only one plot dialog (like in Pcbnew)
clean duplicate code.
Simplify HPGL dialog: plot offet removed and replace by only one option (plot origin to center of sheet or not)
This is surely enought.

Mainly to plot drill maps, but can be used to plot boards, for documentation.
The print svg still exists, but the plot SVG has more options (mirroring, holes in pads),
however  print svg allows color print, and full board printing, and plot does not.

Code cleaning, minor fixes and minor coding style fixes. wxWidgets 2.9.4 compatibility fix( deprecated function MakeModal )

apply DIALOG_SHIM to dialog_lib_edit_text_base and make dialog_lib_edit_pin_base apportion more width for pin name

dialog plot functions: fix compil warnings with wxWidgets 2.8

Eeschema: annotate and netlist dialogs: enhancements.
Minor  coding policy fixes and  changes.

Fix incorrect import of smd pads from Gpcb.
Very minor change in dialog print.

Eeschema, Libedit: Fix bug that can crashes Eeschema: In libedit 2 mandatory fields could be deleted. Fixed now.
Very minor other fixes.

 fix a compil warning.
CvPcb: fix regressions :
 Shows now a void field instead of the dummy footprint name $nonane (whenthere is  no footprint selected in netlist).
 The active footprint selection changes only if a new component is selected from the component file,
 and does not change just when the next component is automatically selected, after a footprint selection.
 Speed up delete association and auto associe.

Add patch from Lorenzo Marcantonio. Fix some warning issues, and zlib issue under Windows (zlib sources added)

All: change MILS_TO_IU_SCALING_FACTOR constant to IU_PER_MILS ( and MM_TO_IU_SCALING_FACTOR to IU_PER_MM)
Also fix bug 985654.

All: change MILS_TO_IU_SCALING_FACTOR constant to MILS_PER_IU  ( and  MM_TO_IU_SCALING_FACTOR to MM_PER_IU)
Also fix bug 985654.

Other scaling factors (MILS_TO_IU_SCALING_FACTOR and DECIMILS_TO_IU_SCALING_FACTOR)
also defined only in convert_to_biu.h.
Allows different scaling value for Gerbview.
Needs more tests.

* Remove internal units from BASE_SCREEN and it's derivatives.
* Remove internal units from EDA_DRAW_FRAME and it's derivatives.
* Use build time code to replace internal units conversions.
* Fix scaling bug in page layout sample window that I created in my
  last commit.

* Move all convert from user to internal units into base_units.cpp.
* Remove internal units parameters from all moved conversion functions.
* Revise all source code that calls the moved conversion functions.
* Remove internal units from all dialog text control helper classes.