add CUPS, fixes #319

README.md

@@ -355,6 +355,7 @@ _Recipe management_
 
 ## Document Archiving
 
+  * [CUPS](https://www.cups.org/) - The Common Unix Print System uses Internet Printing Protocol (IPP) to support printing to local and network printers. ([Source Code](https://www.cups.org/software.php)) `GPLv2` `C`
   * [Paperless](https://github.com/danielquinn/paperless) - Scan, index, and archive all of your paper documents. `GPLv3` `Python`
   * [SANE Network Scanning](http://sane-project.org/) - allow remote clients to access image acquisition devices (scanners) available on the local host. ([Source Code](http://www.sane-project.org/cvs.html)) `GPLv2` `C`