Add a link to the wiki from the install guide for nginx, MariaDB, etc

INSTALL.txt

@@ -51,6 +51,10 @@ php.ini file [or see 'poormancron' in section 8]
 directory/path component in the URL) is preferred. This is REQUIRED if
 you wish to communicate with the Diaspora network.
 
+
+	- For alternative server configurations (such as Nginx server and MariaDB 
+	database engine, refer to the wiki at https://github.com/friendica/friendica/wiki
+
 2. Unpack the Friendica files into the root of your web server document area.
 
 	- If you copy the directory tree to your webserver, make sure