Add default mapping for A command

src/core/DefaultCommandMap.cc

@@ -33,6 +33,7 @@ void DefaultCommandMap::build()
     dcm->add("P", Command::PUT_BEFORE, nullptr, false);
 
     dcm->add("a", Command::ENTER_INSERT_MODE_AFTER_CHAR, nullptr, false);
+    dcm->add("A", Command::ENTER_INSERT_MODE_AFTER_LINE, nullptr, false);
     dcm->add("s", Command::CHANGE_CHAR, nullptr, false);
     dcm->add("d", Command::DELETE_MOTION, motion_map, false);
     dcm->add("dd", Command::DELETE_LINE, nullptr, false);