Changes

Allow location.add to have dLocation input

Example of usage:
- DoSomethingAt
<player.location.add[<player.location.direction.vector>]>

also, fix some tag meta.
 (commit: 3d6d034)

add location.sub,.mul,.div, fix .direction.vector

This adds <location.div> (Divide the location) <location.mul> (Multiply
the location) and <location.sub> (Subtract from the location) to go
along with the existing <location.add>
It also fixes the math in <location.direction.vector>
Example usage:
- explode
<player.location.add[0,1.5,0].add[<player.location.direction.vector.mul[6]>]>
The above will create an explosion 6 blocks directly in front of where
the player is pointing.
 (commit: 2a10d6b)

Cleanup, fix buggy aH.Argument.startsWith(String, Int).
 (commit: 390c2ea)

Allow max 50 tags per argument, allow <>'s to be escaped by using \. Example: - narrate "\<<player.name>\> -\> \<<npc.name>\> 'I have escaped!'" Note: <> character escaping may cause some unforseen problems, please report any odd findings to our GitHub issues page.
 (commit: 473bf93)

Add Operator language.
 (commit: 5910faa)

Add <[email protected][<operator>].to[<element>]> and <[email protected][<operator>].than[<element>]> to allow all the power of an IF in the form of a tag. See notes about escaped <>'s in !lang operator.
 (commit: 379ead5)