Counter more-info: allow to disable "increment/decrement"

[ildar170975]

(probably needs core changes)
Some counters are supposed to be incremented/decremented only by a script/automation .
More-info contains buttons to perform these changes:

Proposal:

1. Add options like enable_increment, enable_decrement to a counter config (true by default).
2. If any option is false - disable a corr. button.

P.S. Probably should be extended to "reset" as well.