Enhanced algorithms to calculate board connections:
    Previously, a track was seen connected to a pad only if the track end is
    exactly on the pad position.
    Now a track is seen connected to a pad if the track end is inside the pad shape.
    Algorithm to calculate pads connections to track is still very fast.
    However some other functions (drag pads, track len calculation ...)
    still need the track end exactly on the pad position.
Dead code removal.

* Replace Eeschema find code with a collector based implementation.
* Fixed a search bug when all subsequent searches of an item would ignore
  the remaining valid child items when an item had more than one child
  item that matched the search criteria.
* Add SCH_FIND_COLLECTOR class to find all items that meet the specified
  search criteria.
* Add SCH_FIND_COLLECT0R_DATA to keep track of information for all matching
  items.
* Use collector to iterate over the list of items that match the search
  criteria rather than trying to start at the last matched item.
* Remove unused searching methods from sheet path and sheet path list
  objects.
* Add replace and replace all functionality to Eeschema find dialog.
* Push matching methods down to EDA_ITEM class so they can be used by
  other derived objects.
* Add method to EDA_ITEM to test if item supports replacing.
* Add flag to find/replace data to support replace feature.
* Disable wild card matching check box when dialog is in replace mode as
  wild card replacement is not supported at this time.
* The usual Doxygen comment and coding policy fixes.

Pcbnew: prepare work on new algos for connections calculations.

the GetPosition() and SetPosition() changes.  It also starts towards making m_Orientation
and m_Thickness fields private with accessors, but does not complete this latter goal.

Pcbnew: Fix issue in Undo/Redo command: for very large boards ( > 20000 items) this command could take a long time. Now fast.

Eeschema: fix crash in intermediate netlist generation when a component has no pins (like logos or images).
Pcbnew: texts in dimensions can be now moved.
Gerbview: fix incorrect number of layers  in export to pcbnew function.

Some code restyling: VECTOR_PCB is an array. Cleanup uncontrolled definitions of abs, max, etc. max is now overloaded function and MAX is a macro.

Metric KiCad work continues. Partially processed D_PAD class. It is still need to be tested including all these import and export procedures...

Pcbnew: remove useless code.
Doc: remobe obsolete reference to MINIZIP (which do not exist now)

* Replace C malloc() and free() functions with C++ new and delete
  operators or the appropriate STL container.
* Add option to end mouse capture function to skip executing the end
  mouse capture callback.
* Lots of coding policy and Doxygen comment goodness.

Add minor enhancements.

General design rules tab converted to nanoscale. A bit of refactorisation in via sizes. And build key is KICAD_NANOMETRE not KICAD_NANOMETRIC (as I stated in previous commit).

Added configuartion option KICAD_NANOMETRIC for this.
* With option set to false: *
- it should work and compile as usual
- some values are saved with decimal point (which should be backward/forward compatible as old versions should just drop fractional part)
* With option set to true: *
- lengths in Global Design Rules should be settable 1nm steps.
FROM/TO_LEGACY_LU(_DBL) macros introduced for easy interconnection between old and new units.

* Use version of DateAndTime that returns a wxString and delete the
  version that takes a char* as it is no longer required.
* Merge StrNumICmp() and StrLenNumICmp() into StrLenNumCmp() to create a
  single function for comparing strings with integers and remove a lot
  of duplicate code.
* Remove unused strupper from string.cpp.
* Use wxArrayString for sorting the EDA_LIST_DIALOG contents.

Pcbnew: Fix a membar issue: Layer setup incorrect location (seems due to an error when using copy/paste editor command)

* Modify algorithm to correctly calculate the virtual drawing size and
  offset required to place the drawing correctly under all conditions.
* Ignore default wxWidgets scroll keys on Windows in EDA_DRAW_PANEL key
  event handler.

Fix bug 887202.

Lee algorithm replaced by a Minimun Spanning Tree algo (using Prim's algorithm ).
Tested on a 5350 pads board, it is more than 100 times faster.
Also fix a crash when clicking on tool  "delete selected items" (main horizontal toolbar),
and remove this tool (currently, no code in Pcbnew for this tool)