Rename the coins folder to networks (#583)

* Rename the coins folder to networks

Ethereum isn't a coin. It's a network.

Resolves #357.

* More renames of coins -> networks in orchestration

* Correct paths in tests/

* cargo fmt

networks/monero/wallet/util/README.md

@@ -0,0 +1,25 @@
+# Monero Wallet Utilities
+
+Additional utility functions for monero-wallet.
+
+This library is isolated as it adds a notable amount of dependencies to the
+tree, and to be a subject to a distinct versioning policy. This library may
+more frequently undergo breaking API changes.
+
+This library is usable under no-std when the `std` feature (on by default) is
+disabled.
+
+### Features
+
+- Support for Monero's seed algorithm
+- Support for Polyseed
+
+### Cargo Features
+
+- `std` (on by default): Enables `std` (and with it, more efficient internal
+  implementations).
+- `compile-time-generators` (on by default): Derives the generators at
+  compile-time so they don't need to be derived at runtime. This is recommended
+  if program size doesn't need to be kept minimal.
+- `multisig`: Adds support for creation of transactions using a threshold
+  multisignature wallet.