rand upgrade to 0.8 tracking issue

[gilescope]

0.7 is 18 months old already. We need to work at this as there's a lot of components and it's going to take some time to settle. There's already additional dependencies versions we're using because we're not upgrading rand.

• upgrade substrate
  • upgrade multihash - upgrading quickcheck to v1 is non-trivial as they removed rnd from being a dependency. ( For context see add back a way to put a bound on numbers generated BurntSushi/quickcheck#267 where even the author is having trouble upgrading )
  • upgrade delak
  • upgrade schnorrkel to 0.10 #10048
  • upgrade libp2p
    • upgrade cuckoofilter - updating rand axiomhq/rust-cuckoofilter#53

[gilescope]

https://github.com/libp2p/rust-libp2p has a RC out. Tried upgrading substrate but there's a few breaking changes there. Will need to dig into if they are significant or not. - roman is working on this.

[gilescope]

Rather than upgrade dalek we should switch to zebra:

• ed25519-zebra #8055