xdo_get_active_modifiers disrupts the conventions of the library

[KoFish]

xdo_get_active_modifiers() returns a pointer to a struct instead of returning the values in arguments like all similar functions in the library does.
By changing this there would be no need for the xdo_active_mods_t struct either.

[jordansissel]

The current method definition is this:

int xdo_get_active_modifiers(const xdo_t *xdo, charcodemap_t **keys, int *nkeys) {

I think 7cf1eaa fixed this.

[jordansissel]

Closing since I think this was resolved in 7cf1eaa; reopen if you feel otherwise :)