Reapi: New func implement

[lozatto]

Restarts entities with the specified classname.
Resets all entities.
Removes a specified number of entities matching the given classname.
Generates a random long integer within a specified range.
Generates a random float within a specified range.
Sets the group trace mask.
Unsets the group trace mask.
Creates a screen shake effect.
Fades the screen for all players.
Fades the screen for a specific player.
Gets the water level at a specific position.
Creates bubbles within a specified area.
Creates a trail of bubbles between two points.
Retrieves the texture type hit by a traceresult, based on start and end positions.

rg_restart_other
rg_reset_entities
rg_remove_other
rg_shared_random_long
rg_shared_random_float
rg_set_group_trace
rg_unset_group_trace
rg_screen_shake
rg_screen_fade_all
rg_screen_fade
rg_water_level
rg_bubbles
rg_bubble_trail
rg_texture_hit