Add component wrapping for non-table values

[hautajoki]

interface Player extends Tag {}
interface Health extends Wrap<number> {}

add function can now only be used with tags

add<Player>(entity); // works with tags
add<Health>(entity); // use set() for components with data

you can now spawn/insert entities with tags (closes #10):

spawn<[Player, Alive]>();
insert<[Player, Alive]>(entity);

// Trailing tags can be omitted
insert<[Name, Health, Player]>(entity, ["Bob", 100]);

also added reset() to restore initial state while keeping references intact - solves the problem presented in #11