MXS-1220: Simplify test creation

The tests now automatically start MaxScale before each test block and stop
it and perform cleanup after the test. This is done by simply calling the
`before.sh` and `after.sh` scripts before each test block.

server/core/test/rest-api/before.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+#
+# This script is run before each test block. It starts MaxScale and waits for it
+# to become responsive.
+#
+
+maxscaledir=$MAXSCALE_DIR
+
+test -z "$MAXSCALE_DIR" && exit 1
+
+# Start MaxScale
+$maxscaledir/bin/maxscale -df $maxscaledir/maxscale.cnf >& $maxscaledir/maxscale.output &
+pid=$!
+
+# Wait for MaxScale to start
+for ((i=0;i<60;i++))
+do
+    $maxscaledir/bin/maxadmin help >& /dev/null && break
+    sleep 0.1
+done