Pin dependencies

[mmagician]

Since arkworks/algebra, poly-commit etc. are moving targets, let's not have our code break because of upstream changes.

This issue is about pinning the dependencies to some specific fork & revision/branch/tag, whatever makes more sense (but should be consistent). Probably revision is best, since we don't have tags that update on a frequent basis, and branches will come from different forks/repos and thus not be consistent.

@DimitrisPapac & @Cesar199999 can you take care of this together please?

[Antonio95]

@mmagician @Cesar199999 Was this solved in #62 ?

[Cesar199999]

@mmagician @Cesar199999 Was this solved in #62 ?

Hmmm, I don't think so. Maybe #62 shouldn't have been merged because the poly-commit revision is wrong, I'll create another PR.

[Antonio95]

Thanks!