session: Add owner's public key into session token

We want to remove all innner ring queries to authenticate
owner by public keys. Therefore we put public keys into
session token. Later public keys could be gathered with NeoID
or other centre of authority.

session/types.proto

@@ -29,4 +29,6 @@ message Token {
     bytes Signature = 6;
     // ID is a token identifier. valid UUIDv4 represented in bytes
     bytes ID = 7 [(gogoproto.customtype) = "TokenID", (gogoproto.nullable) = false];
+    // PublicKeys associated with owner
+    repeated bytes PublicKeys = 8;
 }