* add multilinear_pc barebones

* add multilinear extension commitment scheme

* add unit tests

* temporarily change dependency

* change dependency

* add trim

* remove `get_key`

* use `format` from ark_std

* fmt

* revert prev two

* tweak

* fmt

* Slightly tune the comments

* fmt

Co-authored-by: Weikeng Chen <w.k@berkeley.edu>