- added controls to the values page
- reimplemented mask drawing using GdkPixbuf to make it really always
  pixelated
- fixed size calculations when fmscale is disables
- updated argument loading and saving


git-svn-id: svn://svn.code.sf.net/p/gwyddion/code/trunk/gwyddion@16659 25697fe4-d644-49b8-9d30-be5465f2adf3