Ban time incr

New feature "automatically exponential increasing ban time".
WARNING: by first start the server upgrades sqlite database (table "bans" will recreated with another schema);
Option "bantime.increment" in jail.conf allows to use database for searching of previously banned ip's to increase a default ban time using special formula, by default each next ban increase banTime * 1, 2, 4, 8, 16, 32...
see "jail.conf" for some other options of "bantime.___";
additional we can configure a little randomization of ban time, to prevent "clever" botnets calculate exact time IP can be unbanned.

"bips" is a table with bad ip (and really should be a "sum" of table "bans"), used for:
- read currently banned ips, to be restored after restart;
- used from observer to check ip is "bad" on failure and to increase ban time after banning;
- will be separately treated from purge (corresponding last bantime);