Use apache for tls-proxy ssl termination

Stud is now abandonware (see https://github.com/bumptech/stud) and is
not packaged in xenial. Lets use Apache for SSL termination since its
there already.

Change-Id: Ifcba410f5969521e8b3d30f02795541c1661f83a
diff --git a/functions-common b/functions-common
index 1a4a8f8..4716567 100644
--- a/functions-common
+++ b/functions-common
@@ -2304,6 +2304,16 @@
     fi
 }
 
+# Service wrapper to stop services
+# reload_service service-name
+function reload_service {
+    if [ -x /bin/systemctl ]; then
+        sudo /bin/systemctl reload $1
+    else
+        sudo service $1 reload
+    fi
+}
+
 # Test with a finite retry loop.
 #
 function test_with_retry {