Add the possibility to use transvertr for 28Mhz on tranverter buttons

[SM4IVE]

Its not possible to use 116Mhz as Lo and use Band 1 as 2 m it seems hard coded to 432 Mhz Due the fact i dont want to use the 2M standard for tranverter use. Make it possible to use any band any lo freq in the transverter modul

[rvolchkov]

Implemented