Add command to switch between Nginx and Apache

closes wplib/wplib-box#186

Author: Daryl Lozupone

guest/cli/commands/set-web-server

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+echo "Switching web server to $1"
+
+if [ ! "apache" == "$1" ] && [ ! "nginx" == "$1" ]; then
+    echo 'You must select either nginx or apache'
+    exit 1
+fi
+
+converse="apache"
+if [ 'apache' == $1 ]; then
+    converse='nginx'
+fi
+
+sudo sed -i "s/${converse}/$1/" /etc/supervisor/conf.d/webserver.conf
+
+docker stop ${converse}
+docker start $1