presence: introduce new module parameter force_delete

[eschmidbauer]

• deletes expired presentity records without sending a NOTIFY
• force_delete disabled by default

[eschmidbauer]

@miconda here is PR for new presence parameter

[phil-lavin]

Good timing. Literally just came out of a meeting where the undesirable behavior of repeated terminated NOTIFY messages was discussed. This is a useful addition.

You've changed a lot of whitespace that is not related to this PR. Makes it very difficult to digest :/

Appreciate this isn't your doing and you've just copied the LM_ERR from the rest of the code, but the log levels throughout look a little enthusiastic. These are debug logs - perhaps info at best.

[eschmidbauer]

@phil-lavin sorry about the whitespace changes, I learned from my mistake and will fix whitespace in a separate commit from now on. The only significant change to the code is here:
if (delete_presentity(&pres) < 0) { LM_ERR("Deleting presentity\n"); goto error; }

And if you look at full code, you'll see I just copied it from a few lines below it. You are welcome to change the log levels in a separate PR!
Thanks,
Emmanuel

[miconda]

Thanks, it will be merged!