[chirp_devel] Patch for #8233, Ic-2730

Patch for issue #8233, makes IC-2730 tone modes fully CHIRP compliant. Cross mode now allows Tone->Tone, Tone->DTCS, DTCS>-Tone We need to edit the "DevelopersToneModes" Wiki page, "Icom/Kenwood style" paragraph to note that the Icom IC-2730A actually DOES support two separate TX and RX tones (TON.TSQ mode in the radio). I can do that if permission is granted....:-\