ATC Tree group by FIR/UIR

[KWB]

https://dev.swift-project.org/T635

ATC tree is now grouped by position. This is better than it was before, but it would be very handy if you can group by FIR/UIR.

example:

you fly to LIRF, through LIRR FIR. Atm, you see CTR -- LIRR_N_CTR -- LSAS_CTR APP -- LIMM_N_APP -- LIRR_N_APP TWR -- LIRF_TWR

and if you have a busy time, lots of positions are listed there.

If you can group positions by FIR/UIR, you get something like: LSAS -- LSAS_CTR LIMM -- LIMM_N_CTR -- LIMC_TWR LIRF -- LIRR_N_CTR -- LIRR_N_APP -- LIRF_TWR

which is way easier if you only need the positions to get to LIRF.

difficulty is getting a table with all FIR/UIR's and all of their positions...