[chirp_devel] New 'Information' prompt

Attached for Dan's per-release perusal is a modified version of chirp_common.py and mainapp.py that adds an "Information" prompt. The mods include a new "display_info" config file boolean and new "show_information" /subroutine/ (yeah, I'm one of those guys), as well as a new Help Menu toggle. I have also included two modified drivers that use the new prompt. If Dan blesses this mod, then I need to make sure that the patch process is the same as for a modified driver...