Add option to Auto-Type just the username/password

Fixes #4444

Some websites these days do not present both the "username" and the "password"
input box on the same webpage (e.g. Google, Amazon). So no custom sequence is
possible to enter both the said attributes in one go.

So, two new context menu actions have been added:
1.  Perform Auto-Type of just the username
2.  Perform Auto-Type of just the password

These context menu actions are analogous to "Copy username" and "Copy
password", except it avoids sending all characters via clipboard.

* Create a sub-menu in the Context Menu of Entry.
* The sub-menu offers the following sequences:
    - {USERNAME}
    - {USERNAME}{ENTER}
    - {PASSWORD}
    - {PASSWORD}{ENTER}

src/autotype/AutoType.cpp

@@ -269,7 +269,7 @@ void AutoType::executeAutoTypeActions(const Entry* entry, QWidget* hideWindow, c
 
 /**
  * Single Autotype entry-point function
- * Perfom autotype sequence in the active window
+ * Look up the Auto-Type sequence for the given entry then perfom Auto-Type in the active window
  */
 void AutoType::performAutoType(const Entry* entry, QWidget* hideWindow)
 {
@@ -285,6 +285,19 @@ void AutoType::performAutoType(const Entry* entry, QWidget* hideWindow)
     executeAutoTypeActions(entry, hideWindow, sequences.first());
 }
 
+/**
+ * Extra Autotype entry-point function
+ * Perfom Auto-Type of the directly specified sequence in the active window
+ */
+void AutoType::performAutoTypeWithSequence(const Entry* entry, const QString& sequence, QWidget* hideWindow)
+{
+    if (!m_plugin) {
+        return;
+    }
+
+    executeAutoTypeActions(entry, hideWindow, sequence);
+}
+
 void AutoType::startGlobalAutoType()
 {
     m_windowForGlobal = m_plugin->activeWindow();