* Add general purpose user write permission test function to base
  window class.
* Check user write permissions before saving project, schematic and
  library files.
* Remove displaying file dialog every time the project file is saved.
* Display absolute paths for non-root sheet file in title bar.
* Remove redundant command table entry from schematic editor.
* Remove unused variables to fix GCC 4.6 warnings.
* The usual Doxygen comment and coding style policy fixes.