Safety checks to fix errors from last patch

Fixed issue where indicators were not spawning for fatal damage (bug reported by ZenBreaker)

Improved damage accuracy in some cases for addons that hook into EntityTakeDamage. (Thanks ZenBreaker !)

- Moved the hooking for EntityTakeDamage occur in InitPostEntity, in
most cases, this should guarantee that Hit Numbers is one of the last to
hook to EntityTakeDamage
(What this means is that damage values should be more accurate to how much damage is really being inflicted.)

+ Added much more customizable settings, including:
sv_hitnums_gravity
sv_hitnums_forceinheritance
sv_hitnums_forceoffset_xmin
sv_hitnums_forceoffset_ymin
sv_hitnums_forceoffset_zmin
sv_hitnums_forceoffset_xmax
sv_hitnums_forceoffset_ymax
sv_hitnums_forceoffset_zmax
+ Added a debug mode that displays performance information.
(hitnums_debugmode)
- Some more optimizations to cut performance cost, indicator updating
performance has been halfed! Indicator creation is also much less
taxing.

+ Added animations! Select between 3 different style of animations + no animation. (See sv_hitnums_animation)
- Fixed error caused when improperly setting sv_hitnums_critmode

- Reworked solution for corrupted settings.txt

- Some indicator rendering optimizations.
- Fixed a potential bug regarding colours. Nothing really changelog-worthy, though.

+ Added ability for clients to toggle Hit Numbers in Sandbox gamemodes via spawn 'Q' menu. (Available under Utilities tab)
- Server settings are now saved. No need to use server.cfg anymore! (under garrysmod/data/hitnumbers)
- Now using UDP networking, should be relatively much less laggy network-wise. (Ready for next big Garry's Mod update)
- Some code formatting no one really cares about.

- Work-around for bad crowbar damage position. Now uses a trace to determine where the damage is being dealt. It's not perfect, but it works well enough.
- Small optimizations
- Loaded console message