Merge branch 'grc' of http://gnuradio.org/git/jblum into master

* 'grc' of http://gnuradio.org/git/jblum:
  use show signal to perform initial gui update
  Fixed the usrp and usrp2 probe scripts to work with the new gui param api.
  propsdialog tweaks
  more code cleanup for properties dialog
  Rework the params/properties dialog and param gui class:
  renamed params dialog to props dialog
  remove unused imports, copyright date update, tweak
  Created recursive create labels and shapes method for gui element.
  replaced dict[rot] storage of areas and lines with a single list for the current rotation
  standardized the Element inheritance __init__ usage in gui
  better error msg for empty statements
  Implement a recursive validation api in the base Element class.