* Add footprint methods to PCB_IO.
* Add FP_CACHE and FP_CACHE_ITEM for handling new footprint library design.
* Add code to save legacy libraries in new format.
* Change behavior of BOARD_ITEM::GetLayerName() to return the default layer
  name when the item does not have a BOARD as a parent.
* Minor changes to the module output formatter when writing to module library
  files (no BOARD as parent).
* Add new (and some that I forgot along the way) CMake flags to
  EDA_BASE_FRAME::CopyVersionInfoToClipboard().
* Add -Wno-narrowing to GCC flags to stop GCC 4.7 from complaining about
  a conversion from int to unsigned in the Boost polygon library.
* Add INPUT_STREAM_READER to richio.cpp to allow using any object derived
  from wxInputStream as a LINE_READER (needs to be validated).