Crossbeam!

When working on an EDR project I noticed that MPSC has a bug that has gone unfixed for 5 years causing panics in some cases while calling recv_timeout on an mpsc.

The recommended fix is to move to Crossbeam so that's what this does. This is obviously a breaking change but I didn't see another way forward. Also Crossbeam supports select! which is pretty neat.

Refactors and Ease of Use

Refactored lots of things to make it easier to use and be more Rustic.

CDHash Fix

Fixed a bug where 0s weren't prepended for each byte when parsing the CDHash.

This meant that CDHashes were not consistent in length, and incorrect compared to codesign. As an example here is the CDHash of bash according to codesign, and old endpointsecurity.

ES:   27 C8 F0 D6 33 7C  6 84 CE C0  0 48 E0 FA CE ED FD 57  2 8E
CS:   27 c8 f0 d6 33 7c 06 84 ce c0 00 48 e0 fa ce ed fd 57 02 8e

This is now fixed and CDHashes are now always 40 characters.