Add links to protocol specs (which are out of date).

bramble-api/src/main/java/org/briarproject/bramble/api/crypto/KeyAgreementCrypto.java

 package org.briarproject.bramble.api.crypto;
 
+/**
+ * Crypto operations for the key agreement protocol - see
+ * https://code.briarproject.org/akwizgran/briar-spec/blob/master/protocols/BQP.md
+ */
 public interface KeyAgreementCrypto {
 
 	/**
@@ -21,8 +25,6 @@ public interface KeyAgreementCrypto {
 
 	/**
 	 * Derives a commitment to the provided public key.
-	 * <p/>
-	 * Used by the key exchange protocol.
 	 *
 	 * @param publicKey the public key
 	 * @return the commitment to the provided public key.
@@ -31,8 +33,6 @@ public interface KeyAgreementCrypto {
 
 	/**
 	 * Derives the content of a confirmation record.
-	 * <p/>
-	 * Used by the key exchange protocol.
 	 *
 	 * @param sharedSecret the common shared secret
 	 * @param theirPayload the key exchange payload of the remote party

bramble-api/src/main/java/org/briarproject/bramble/api/crypto/TransportCrypto.java

@@ -3,13 +3,15 @@ package org.briarproject.bramble.api.crypto;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.transport.TransportKeys;
 
+/**
+ * Crypto operations for the transport security protocol - see
+ * https://code.briarproject.org/akwizgran/briar-spec/blob/master/protocols/BTP.md
+ */
 public interface TransportCrypto {
 
 	/**
 	 * Derives initial transport keys for the given transport in the given
 	 * rotation period from the given master secret.
-	 * <p/>
-	 * Used by the transport security protocol.
 	 *
 	 * @param alice whether the keys are for use by Alice or Bob.
 	 */
@@ -18,16 +20,12 @@ public interface TransportCrypto {
 
 	/**
 	 * Rotates the given transport keys to the given rotation period. If the
-	 * keys are for a future rotation period they are not rotated.
-	 * <p/>
-	 * Used by the transport security protocol.
+	 * keys are for the given period or any later period they are not rotated.
 	 */
 	TransportKeys rotateTransportKeys(TransportKeys k, long rotationPeriod);
 
 	/**
 	 * Encodes the pseudo-random tag that is used to recognise a stream.
-	 * <p/>
-	 * Used by the transport security protocol.
 	 */
 	void encodeTag(byte[] tag, SecretKey tagKey, int protocolVersion,
 			long streamNumber);