Serious lib

• Added add_motion and set_motion. Use FM player data modification to apply motion to the player. Take "vector" parameter which requires a string of relative coordinates. Example:

function add_motion {"vector":"~ ~1 ~"}

• Added hilariously bad raycast functions, don't bother with them <3
• Added relative_tp. Teleports the executing entity relative to a starting position. Can also use relative_tp_data to use stored data values. Example:

function relative_tp {"start_pos":[0,0,0],"end_pos":[0,10,0]}

• Added a couple advancements and predicates I use often.