Added optional requirements file for pip lovers.
Added optional requirements file for pip lovers.

mattcaldwell/djangopypi,hsmade/djangopypi2,popen2/djangopypi2,disqus/djangopypi,pitrho/djangopypi2,hsmade/djangopypi2,disqus/djangopypi,pitrho/djangopypi2,EightMedia/djangopypi,popen2/djangopypi2,EightMedia/djangopypi,benliles/djangopypi