Remove Monero as a dependency

Introduces missing CLSAG checks. The only difference now should be the 
additional rejection of torsioned points, which is relevant to 
https://github.com/serai-dex/serai/issues/25. Considering this is only 
currently used for FROST verification, this should be fine.

Closes https://github.com/serai-dex/serai/issues/19 by making it 
irrelevant.

Increases priority of https://github.com/serai-dex/serai/issues/68, as 
now it's used for the BP generators which are done at first-proof.

Also merges BP's stricter hash_to_point with the library's, since CLSAG 
has the same bound.

coins/monero/src/tests/clsag.rs

@@ -74,8 +74,6 @@ fn clsag() {
     )
     .swap_remove(0);
     clsag.verify(&ring, &image, &pseudo_out, &msg).unwrap();
-    #[cfg(feature = "experimental")]
-    clsag.rust_verify(&ring, &image, &pseudo_out, &msg).unwrap();
   }
 }