Add missing features from LLHL/EHLL

[rtxa]

There are some missing features from LLHL with the AG version, let's make clear which are:

• Enforce minimum delay settings for HLTVs (minimum of 30 seconds)
• Enforce maximum number of HLTV (default: 2)
• Block model change when a match has started
• Block displaying / Don't reveal Location/HP/Weapon messages from match players to spectators.
• Ghostmine blocker (Fix explosions can go through walls in certain cases). Gameplay changer maybe?
• FOV limiter (disabled by default). Useful to block scripts for zooming on weapons like Gauss to kill from far distances (bootbox, stalkx, etc.)
• llhl_match_manager command for administrators (Not sure how it works)
• Score penalty for changing model during a match (Enabled by default). Exploit used for some players to avoid death maybe?
• (Unlikely to implement) Random spawns
• (Unlikely to implement) Block players using Family Sharing. Requires adding another module. Maybe not worth the hassle.

From EHLL:

• force_hltv Sends spectators to hltv server. Maybe this doesn't work anymore because of latest change on client commands not allowing to redirect to other server.
• CVar checker
• (Unlikely to implement) Precache of clan models (Probably in some cfg file list). Not very useful because clients can override these models for better sight.

Some ideas by me:

• Instead of enforcing sound file check (kick), just check it silently and alert players or server administrator about it.