Add forced discard after 10 delivery failures, don't crash when a search doesn't return an account

src/controller/api/accounts.c

@@ -85,7 +85,9 @@ static bool handle_search( struct http_request* req )
 	}
 
 	fprintf( f, "[" );
-	api_Account_write(a,f,1);
+	if( a ) {
+		api_Account_write(a,f,1);
+	}
 	fprintf( f, "]" );
 
 	account_free(a);

src/controller/outbox.c

@@ -122,6 +122,11 @@ static bool process_envelope( int id )
 		if( env->retry_after ) {
 			env->retries += 1;
 		}
+		if( env->retries > 10 ) {
+			// Force discard after 10 delivery attempts
+			// TODO: change this to a configuration option
+			env->sent = true;
+		}
 		env->retry_after = time(NULL) + 60 * ( env->retries + 1 ) * ( env->retries + 1 );
 		outbox_envelope_save(env);
 	}

src/ffdb

@@ -1 +1 @@
-Subproject commit 1a630944a79aa31d95be7ee1b37a37f8556cd1c5
+Subproject commit 5ed4d47ba63963edf8373dbb1e095060888abd6e