Update red5.spec for 1.0.3-RELEASE and add a auto-build-script

I updated red5.spec for 1.0.3-RELEASE since red5 infrastructure had changed compared with 1.0.1. See also howto.txt included in this PR to build RPM and install it.

I will update wiki as follows after this PR would be merged.

* https://code.google.com/p/red5/wiki/RPM_HowTo