Small enhancements

[SwoopX]

• Enable group creation for Sonoff SNZB-01 (Sonoff SNZB-01 Unable to Pair or Add to group #3490)
• Unify debug output for button presses
• Remove MFC check for Elko Super TR attribute reports (Get Elko Thermostat to show temperature for floor sensor #3123)
• Expose RConfigMode and correct attribute for Elko Super TR (Get Elko Thermostat to show temperature for floor sensor #3123)
• Fix typo to create only 1 switch resource for Namron switches
• Make RConfigMode usable for Elko Super TR to turn device on/off (Get Elko Thermostat to show temperature for floor sensor #3123)
• Remove thermostat mode binding for Elko Super TR (Get Elko Thermostat to show temperature for floor sensor #3123)
• Enable battery attribute reporting for SZ-DWS04 (Constant LOW Battery Warning on Sercomm SZ-DWS04 Micro Door Window Sensor #3576)
• Added missing "windowopen" value for Danfoss TRV (Danfoss Ally reporting NULL in windowopen? #3591)
• Guard against empty simple descriptors

[GeoCyberwolf]

Awesome, thank you for doing this! :)

I can test this if you want, as I have the SNZB-01 switches. I may need some help compiling from source though, as it's not something I have done much of.

[manup]

I'd like to merge this PR for the stable release, can you please base this on the current master to solve merge conflicts?

[SwoopX]

@manup Done!