Telemenu: Some bug fixes and small improvements

This update feature :

-  The use of float version of origin natives instead of integer version :
This mainly fix problems encountered due to imprecision of integer origin natives : If the origin is saved by an alive player on the ground, sometimes the teleported player can be stuck on ground, especially in slopes.

- The ability to save an origin from an alive player in a crouched area or in a crouch state and teleport to it without risking stuck problems.

- The ability to save the view and use it during teleportion :
This feature allow you to save the view angles of the player who save the origin and apply them at teleportation on player's angles of teleported player.

- The use of charsmax in place of hardcoded buffer lengths.

- The switch format to formatex.

Tested on Counter-Strike 1.6.
It need testing with other games, i think.