Fix redhat package to build and run cleanly for current v2.x.x branch

The first four commits are just fixes to get current spec file to build.

The rest of the commits follows up the discussion on http://lists.freeradius.org/pipermail/freeradius-users/2013-May/066447.html. On the upside, these commits made the RPM more generic and future-safe (e.g. from module addition) by:
- removing most patches from the spec and redhat directory, leaving only freeradius-cert-config.patch
- include all modules (including future new ones, should they be added) in the main freeradius package by using wildcards in %files
- leaving all existing module packages (e.g. freeradius-mysql) in tact, but without any files in it, so that a normal upgrade (e.g. freeradius + freeradius-mysql 2.1.12 -> freeradius + freeradius-mysql 2.2.1) still works.
- removing most old changelogs

The downside is that installling the resulting RPM would require the user having all the prequisite packages (e.g. mysql libs) installed whether they will use it or not. But then again, it should not matter since they will already need the prequisites installed to be able to build the RPM package anyway.

Tested to build and run on Centos5 and Centos6.