Installing libcups2-dev instead of libcupsys2-dev in 13.04
libcupsys2-dev is old(2008) and don't exist in ubuntu 10.04+. Installing libcups2-dev instad
libcupsys2-dev is outdated(2008). Installing libcups2-dev instead if not libcupsys2-dev is found
Merge pull request #3 from Joachricar/master

Install libcups2-dev if it cant find libcupsys2-dev, otherwise bjnp can't build.

Hi Joachricar, I am going pull this in however at present I no longer have an MP620 to work with, it literally broke over the weekend. So for lack of a general ability to test I will assume that all is working :P

I have also pushed a dev branch that I was working on over the past few weeks to make things go with Ubuntu 13.04, I would be curious if you could try out that branch and let me know if it is working for you? branch is "dev-cups-121". The branch should work, it was working for me, however it should NOT WORK with Ubuntu < 12.04.