digital: made the demod examples clearer
grc: Fixed Bug #485 by gracefully exiting when user sets GR_DONT_LOAD_PREFS=1 GRC_BLOCKS_PATH=
core: added operator == for tags
core: added remove_tag_item()
Merge remote-tracking branch 'mbant/demod_examples'
Merge remote-tracking branch 'mbant/fix485'
Merge remote-tracking branch 'mbant/equal_for_tags'