- Merged config option knockback_left from Hercules
  * Now the default direction is "east" and consequently the knockback direction is "west" when standing
  * This means if the source cell (ground target center or position of caster) is on the same cell as the target, it will be knocked back to the west
  * This also can effect other things like how an object is placed when cast on the cell you are currently standing on
  * If you disable the option it will use the old behavior and use the direction of the unit as default direction (and backwards as knock direction)
  * Special thanks to kisuka and Michieru for the original implementation: https://github.com/HerculesWS/Hercules/commit/2b8d5013ea8ba9904d157c773f12495bbca8ca80
- Optimized the knockback / instant movement code
  * clif_blown will now call both clif_slide and then clif_fixpos, this is what Aegis does when any instant movement effect occurs and ensures proper updating of the position
  * skill_blown will call clif_blown and ensures the correct client information already, so it's no longer necessary to manually call clif_slide and clif_fixpos after it
  * replaced all calls of clif_slide and then clif_fixpos in row with a single call of clif_blown, makes the code look a lot cleaner
  * I tested over 20 knockback situations including knockback of frozen target and it worked fine for me, please report if there is still anything wrong (was why fixpos commented in the first place?)
Merge remote-tracking branch 'upstream/master'