* Added space between channels in mixers tab, amount defined by MIX_ROW_HEIGHT_INCREASE
* Added highlighting of selected channel when used as source in other channels (Ctrl+T or context menu->Toogle highlight)
* Added leading zero to channel name for ch_number < 10 (better alignment for CH1 to CH9)
Fixes suggested by Bertrand. ExtraChannels not yet removed
Merge pull request #976 from projectkk2glider/companion_mixes_tab_highlights

Two visual enhancements to mixes tab in companion