updated conv_ttl_rs485.vhd to the one from DB-new-conv-common-gw that treats the different RTMs

testbench wip

- updated .xise to include simulation

added to the top entity the pcb version number coming from the pcb. connected this to conv-common-gw for hwvers register

Moved inverter channel logic inside conv-common-gw. This includes inv-channel LEDs. Also now using negative logic for all LEDs

Send front and rear pulse to conv-common-gw, not just the result of their OR operation. This is for implementing separate front and rear counters