Added few commands

Added /fly, /vanish, /tpahere, /tphere, /tpdeny 
Added /spawn [playername]
Enabled /tps from console
You should combine these two into a single table:
```lua
local TeleportRequests = {}
...
TeleportRequests[OtherPlayer:GetUniqueID()] = {Type = "tpa", Destination = Player:GetUniqueID() }
```
Feel free to use strings for Type, they are more obvious in code and they have the same performance, comparison-wise, as numbers in Lua.