Timer interval, Waterball, Crimson Fire Formation and boss walk delay updates
- Reduced the timer interval from 50ms to 20ms (official value)
  * For a long time it is well known that the Aegis interval is 20ms, but devs have been hesitant to set it to that out of performance reasons; these days however, machines are better and there aren't really many 2000+ player servers anymore, so a 20ms interval is actually quite viable now.
  * Setting the interval to 20ms makes the server perfectly in sync with the client that expects the server to have a delay of no longer than 20ms.
  * All skills that are "chain-able" on official servers will now also be 100% chain-able here (previously it just worked to 40%), assuming there is no lag
  * Skills with cast time will no longer go off 30ms later than officially
  * Several others improvements in regards of client-server sync (timers are used almost everywhere)
  * This might increase the CPU usage by up to ~50%, if you have trouble running your server with this, you can increase it again in timer.c (TIMER_MIN_INTERVAL)
- Strongly improved the Waterball implementation (bugreport:9382)
  * The interval between Waterballs is now 150ms (previously 125ms); due to the timer interval it will alternate between 140ms and 160ms (yes, this is official)
  * While the Waterball effect is active, players and non-boss monsters can no longer walk
  * Added a server-sided canact delay each time a Waterball is shot, which is equal to the one the client gives; this is to prevent hackers from being able to mass-cast Waterball; you can still multi-cast Waterball if your aMotion is shorter than the Waterball interval (i.e. 186 ASPD or higher)
  * The Waterball effect is no longer canceled when the target hides behind an obstacle, but no waterballs will fly and no damage will be applied; walkdelay will remain, but there won't be any canact delay for the caster (meaning he can cast another spell); if the target comes out of its cover during the duration, it will be hit again (this also fixes an exploit against MVPs)
  * Waterball now has a max duration of 10 seconds, even if more water cells are available, the effect will stop; this means that level 10 monster water ball will now only hit up to 67 times
- Fixed Crimson Fire Formation having a knock-back effect although it shouldn't (bugreport:6949)
  * It will hit once every 20ms with no knock-back, regardless of whether the target is undead, non-undead or a player
  * If you want to it to display more "fluently" you would need to set the SKILLUNITTIMER_INTERVAL in skill.c to 20ms, but the performance loss is pretty big for something only this skill and Firewall would benefit from
- Bosses are now able to ignore skill-induced walk delay (#100)
  * They can for example walk after casting Sonic Blow and Waterball (see above)
- Minor description improvements