Added true RIT functionality
Added true RIT functionality (adjustable RX offset) (2 Function Button presses)
The existing 'RIT' function, based on switching VFOs, is now called "SPLIT" (3 presses)
Mode selection (4 presses) can now also be used to select CWL and CWU
Major code cleanup to reduce memory usage
Inserted some delay in various routines to prevent buzzing sound in SETTINGS menu