Release notes for firmware ver. SW00294-03.81

Supported devices:
- Z-TWS4/Z-PASS2-S/S6001-RTU
- Z-PASS2-S-R01
- Z-PASS2-S-IO
- Z-PASS2-S-IO-4G-EU
- Z-PASS2-S-IO-4GWW
- Z-TWS4-IO
- S6001-RTU-4GWW

FIX:
- fix of receiving messages with text longer than 160 characters. Messages are now received anyway but truncated to the supported number of characters, previously the message was not received.