Add --continue argument

The monitor will exit when key is pressed.
Add --continue argument and if it is set to "true", the monitor will
continue after key is pressed.

This is useful in cases to monitor a button presses.
E.g. It can be used to monitor ID button and start a system unit
everytime when the button is pressed.

This argument is optional so it does not break the current code.

Tested: With "--continue=true", the monitor does not exit when the key
        is pressed.
        Without the argument of if it is set to other strings, the
        monitor exits after the key is pressed.

Change-Id: I4f2ca16d7b26e10397181c83c2c5947ed5ce091f
Signed-off-by: Lei YU <mine260309@gmail.com>
diff --git a/monitor.cpp b/monitor.cpp
index 5bc4742..159127d 100644
--- a/monitor.cpp
+++ b/monitor.cpp
@@ -86,9 +86,12 @@
                     bus.call_noreply(method);
                 }
 
-                // This marks the completion of handling the gpio assertion
-                // and the app can exit
-                complete = true;
+                if (!continueAfterKeyPress)
+                {
+                    // This marks the completion of handling the gpio assertion
+                    // and the app can exit
+                    complete = true;
+                }
                 return;
             }
         }