Factor out transport crypto from CryptoComponent.

.../org/briarproject/bramble/api/crypto/CryptoComponent.java

.../org/briarproject/bramble/api/crypto/TransportCrypto.java

.../org/briarproject/bramble/crypto/CryptoComponentImpl.java

...in/java/org/briarproject/bramble/crypto/CryptoModule.java

...iarproject/bramble/crypto/StreamEncrypterFactoryImpl.java

.../org/briarproject/bramble/crypto/TransportCryptoImpl.java

...ect/bramble/transport/TransportKeyManagerFactoryImpl.java

...iarproject/bramble/transport/TransportKeyManagerImpl.java

...va/org/briarproject/bramble/crypto/KeyDerivationTest.java

...java/org/briarproject/bramble/crypto/TagEncodingTest.java

...va/org/briarproject/bramble/sync/SyncIntegrationTest.java

...roject/bramble/transport/TransportKeyManagerImplTest.java