Publish ssz_types (and deps) to crates.io (#468)

* Rename `hashing` crate to `eth2_hashing`

* Add license, desc to eth2_hashing Cargo.toml

* Remove merkle root from eth2 hashing

* Remove old benches folder (zombied from old branch)

* Add docs to eth2_hashing

* Prepare tree_hash for publishing on crates.io

* Update deps to use crates.io instead of paths

* Update all crates to pull ssz from crates.io

* Remove cached_tree_hash, add patches to manifest

* Fix compile error in benches

* Remove unused code

* Fix fake_crypto compile error

eth2/utils/tree_hash/Cargo.toml

@@ -1,8 +1,10 @@
 [package]
 name = "tree_hash"
-version = "0.1.0"
+version = "0.1.1"
 authors = ["Paul Hauner <paul@paulhauner.com>"]
 edition = "2018"
+license = "Apache-2.0"
+description = "Efficient Merkle-hashing as used in Ethereum 2.0"
 
 [[bench]]
 name = "benches"
@@ -11,11 +13,10 @@ harness = false
 [dev-dependencies]
 criterion = "0.2"
 rand = "0.7"
-tree_hash_derive = { path = "../tree_hash_derive" }
+tree_hash_derive = "0.2"
 types = { path = "../../types" }
 
 [dependencies]
 ethereum-types = "0.6"
-hashing = { path = "../hashing" }
-int_to_bytes = { path = "../int_to_bytes" }
+eth2_hashing = "0.1"
 lazy_static = "0.1"