[enhancement] Option to ignore contact/group in record rules

[StanTody]

As for now EVERY call is recorded (and some are deleted on call end), I suggest to current states of the recording rules (on/off) to add third - "ignore".

In that way we will save battery, space, fragmentation and "write cycles" of the internal memory (when having long dialogues with our wifes and children, for example ;) ).