Some types used for encryption related tasks need to be used across more
internal crates than expected, so a few have been moved and renamed for
clarity.
* Rename the key_algorithms module in ruma-identifiers-validation to crypto_algorithms
* Move ruma_events::Algorithm to ruma-identifiers-validation and rename it EventEncryptionAlgorithm
* Move DeviceKeys from ruma-client-api to ruma-common
