Update deps, new Map struct

[RoDmitry]

• Updated criterion, wyhash, rkyv;
• Fixed benches (also black_box was in the wrong place);
• New Map struct, which is more compact than MapWithDict if 64-bit values are used;
• Added Mphf doc comment.

Closes: #4, #5

[RoDmitry]

I have also tried Map which uses tuple for storage, but somehow it's slower.

[RoDmitry]

ArchivedMap which uses tuple for storage appeared to be faster in a real usage in a memory intensive application, so reverted back to it. And ArchivedHashMap from rkyv is even faster. Looks like benches don't show the real performance.