Add support for the use of other enum sets in the enum_set! macro. (C… #79

Job	Run time
build_no_std	20s
build_msrv	2m 21s
build (stable)	16s
build_msrv (--features serde)	2m 15s
build_msrv_all_features	2m 7s
build (stable, --features serde)	19s
build_msrv (--features alloc)	2m 12s
test_trybuild	37s
build (stable, --features alloc)	15s
build_msrv (--release --features serde,alloc)	2m 37s
build (stable, --features proc-macro-crate)	18s
build (stable, --features serde,alloc,proc-macro-crate)	17s
build (stable, --release --features serde,alloc,proc-macro-crate)	44s
build (beta)	22s
build (beta, --features serde)	23s
build (beta, --features alloc)	22s
build (beta, --features proc-macro-crate)	24s
build (beta, --features serde,alloc,proc-macro-crate)	25s
build (beta, --release --features serde,alloc,proc-macro-crate)	42s
build (nightly)	20s
build (nightly, --features serde)	21s
build (nightly, --features alloc)	20s
build (nightly, --features proc-macro-crate)	22s
build (nightly, --features serde,alloc,proc-macro-crate)	22s
build (nightly, --release --features serde,alloc,proc-macro-crate)	46s
	19m 47s

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