Feature/rpm 0.1

My doubt is about the sequence from the point of view of the user generating the RPM. I mean:

* The user runs rpmbuild and some ".spec magic" invokes the package.sh script to download Flume and package it along Cygnus
* The user runs package.sh to download Flume, then invokes (as second manual step) rpmbuild to create the RPM incluing both Flume and Cygnus.