Switching to OpenGL using shaders backend on the fly (changed keyboard shortcuts: different backends are available using Alt+F9..F12).

Shader's parameters are stored in VBO_ITEM. Changed VBO_ITEM data structure. Added UseShader() function for selecting shader for a given VBO_ITEM.
Added one main vertex & fragment shader program to be used for with all kinds of items (type of shader is selected using attributes that are stored in VBO). Currently available shaders are: at-least-1px-width line, filled circle and stroked circle.
Removed unnecessary param (aDepthOffset) from a few functions (OPENGL_GAL::drawSemiCircle(), OPENGL_GAL::drawLineCap()). Removed function OPENGL_GAL::DrawRoundedSegment(). Changed some asserts to debug info or error log.

Display linking errors in debug mode for shaders. Added SHADER::GetAttribute() function for getting shaders attribute location.

Added functionality for transformation of VBO vertices, extended functions like translate, rotate, scale using glm library. Removed D() macro, as it was not used, but in conflict with glm library. Added VBO_ITEMs for circles, semicircles. Now almost everything is drawn using VBO (besides polygons and grid).

Items are not recached until GAL is changed (earlier it was done on every rendering backend switch).

* Create separate NETLIST object to hold contents of netlist files.
* Read entire netlist and footprint link files before making applying
  changes to board.
* Add BOARD::ReplaceNetlist() function to eliminate the calls between the
  NETLIST_READER, PCB_EDIT_FRAME, and BOARD objects.
* Change placement of new components below the center of the current board
  or in the center of the page if the BOARD is empty.
* Add dry run option to netlist dialog to print changes to message control
  without making changes.
* Add button to netlist dialog to allow saving contents of message control
  to a file.
* Eliminate the need to compile netlist_reader_*.cpp in both CvPcb and Pcbnew.
* Add netlist_reader_*.cpp to the pcbcommon library.
* Remove redundant load component link file code from CvPcb.
* Modify CvPcb new to work with the new NETLIST_READER object.
* Add compare() function and < and == operators to FPID object.
* Add REPORTER class to hide an underlying string writing implementation for
  use in low level objects.  Thank you Dick for the idea.
* Lots of minor coding policy, Doxygen comment, and missing license fixes.

pcb_parser failed on (fill yes (arc_segments 16) (thermal_gap 1.99898) (thermal_bridge_width 1.99898))
See http://tech.groups.yahoo.com/group/kicad-users/message/15105

Removed BeginLayer and EndLayer functions. Resolved Cairo layers drawing problem in a different way.