Modular KiCad Blueprint Milestone B), major portions:
  *) 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.