Support for multiple players

[alphappy]

Add support for multiple players running macros simultaneously.

Possible designs:

1. Add an optional flag to each line that indicates which player the line affects, default to 1 (or a macro-level default). This is incredibly cumbersome to write a macro and would require refactoring how exactly a macro tick is decided.
2. Add an interface-level setting for deciding which player runs which macro. This requires making the library and macros non-static and makes the interface more complicated.
3. Add an extension to >execute which allows specifying player. This requires making the library and macros non-static. >execute does not tick and so simultaneously running different macros for different players would not be complicated.

[alphappy]

Dependent on #7

[RPink47]

number 3 is probably the most viable, for number 1, the macro could remember which players were already ticked, and continue until it hits a player it already ticked.

[RPink47]

This may also depend on #8

[RPink47]

Ideally you should be able to execute the macro as the next player, previous player, second next player, or any player number. Aka player relative to me, and absolute.