Tame the mycroft.sh script

The mycroft.sh script uses the 'screen' command to run the various
processes that make up Mycroft Core.  When they are stopped with
"./mycroft.sh stop", it was using the screen 'quit' command.  This
ends the process abruptly, not allowing services to shutdown
cleanly.

This changes it to send a shutdown request first, equivalent of a
Ctrl-C.  If the service doesn't shutdown after 2 seconds it is
then killed.

This specifically prevents issues where a skill expected and did
not receive a call to the shutdown() method.

mycroft.sh

@@ -111,7 +111,26 @@ function start-mycroft-debug {
 function stop-screen {
   for i in $(screen -ls "$1"); do
     if echo $i | grep -q $1; then
-      screen -XS $i quit && echo "Stopped $1" || echo "Could not stop $1"
+       screen -S $i -X stuff '^C'&& echo "Stopping $1" || echo "Cound not stop $1"
+
+       # Give process 2 secs to shutdown
+       c=1
+       while [ $c -le 20 ]
+       do
+           if ! screen -list | grep -q "$i";
+           then
+              c=999
+           else
+              (( c++ ))
+              sleep 0.1
+           fi
+       done
+
+       # Kill if still up
+       if screen -list | grep -q "$i";
+       then
+           screen -XS $i quit && echo "Killed $1" || echo "Could not kill $1"
+       fi
     fi
   done
 }