Eeschema: Fix some issues (all connections showed as not connected, DRC and NETLIST errors if all sheets in a hierarchy were not open) due to the fact the pointer of a schematic component to its part lib was calculated too late (or never calculated).

Eeschema: fix incorrect value of m_Flags member (must be 0) of schematic components after loading a schematic file.
Previously,  m_Flags was set to IS_CHANGED, which is incorrect.

  *) When kicad.exe closes a project, close any open KIFACEs so that they cannot
     get disassociated from their true PROJECT.
  *) Allow loading eeschema library editor from kicad.exe
  *) Allow loading pcbnew library editor from kicad.exe
  *) Rename LIB_COMPONENT to LIB_PART.
  *) Add class PART_LIBS, and PART_LIB.
  *) Make PART_LIBS non-global, i.e. PROJECT specific.
  *) Implement "data on demand" for PART_LIBS
  *) Implement "data on demand" for schematic SEARCH_STACK.
  *) Use RSTRINGs to retain eeschema editor's notion of last library and part being edited.
  *) Get rid of library search on every SCH_COMPONENT::Draw() call, instead use
     a weak pointer.
  *) Remove all chdir() calls so projects don't need to be CWD.
  *) Romove APPEND support from OpenProjectFiles().
  *) Make OpenProjectFiles() robust, even for creating new projects.
  *) Load EESCHEMA colors in the KIWAY::OnKiwayStart() rather in window open,
     and save them in the .eeschema config file, not in the project file.
  *) Fix bug with wxDir() while accessing protected dirs in kicad.exe
  *) Consolidate template copying into PROJECT class, not in kicad.exe source.
  *) Generally untangle eeschema, making its libraries not global but rather
     held in the PROJECT.

* Remap configuration button on toolbar to launch footprint library table
  editor.
* Remove legacy footprint library path dialog from CVPCB_MAINFRAME.
* Remove unused event ID ID_CVPCB_CREATE_CONFIGWINDOW.
* Minor coding policy fixes.

Pcbnew: add drc test for texts on copper layer (only in full drc test, not in on line drc), from a patch sent by Simon Schumann
Add EDA_TEXT::TransformTextShapeToSegmentList function to export a list of segments used to draw/plot the text.

* Improve footprint text properties layout.
* Use wxStdDialogButtonSizer instead of manually laid out buttons to improve
  platform UI consistency.

Pcbnew, Cvpcb: fix Bug #1355883 . Due to a missing call to a delete operator in CMP_READER class (also creates memory leak).

3d viewer: fix a (minor) bug when run from cvpcb or modedit: the footprint is now centered on Z axis
Better setup for lights, which gives a better rendering

2) LIB_RECTANGLE and related classes sscanf data read from a file using "%s"
without field limits, which can cause problems with malformed/really long
inputs.

3) If some of the optional fields in a lib line are missing, "tmp" can remain
uninitialized.

3D viewer: Parallelized 3D model vertex normal calculations to use all available CPU cores for significant speedup.

Pcbnew: Commit patch (with very minor changes) about SVG file export with the layers ordered from bottom to top. ( bug 1286646 ), from Thiadmer Riemersma.

3dviewer: back to double (from float) in class S3D_MASTER for 3 members (m_MatScale, m_MatRotation, m_MatPosition) which are used in dialogs and r/w file functions, which expect double.
Using float create minor but unwanted issues in  r/w file functions.
S3D_MATERIAL: enable all color options: if a 3d shape has bad color parameters, the shape must be modified, not the 3d rendering.
The rendering now matches what we see in other vrml viewer like FreeCAD.
Some minor coding style fixes.

Items are either dragged by their origin or moved by a vector (depending on the number of selected items) (GAL).

common.cpp: remove useless  warning on wxWidgets < 3.0 about --with-gtkprint build option: on  wxWidgets < 3.0 on Linux the print function does not work even with this build option.

3D viewer: move helper functions from 3d_draw.cpp to 3d_draw_helper_functions.cpp. Add comments in .h sources. Better management of background color. coding style fixes.