packaging: Move DEB and RPM packaging to Maven and remove Ant configuration

Packaging was the only thing we still did (partially) through ant. Our
packaging is however mostly about putting the right files together and
calling the native packaging tools, and that we can do just as easily
from Maven.

This patch moves the RPM and DEB packaging to the fhs and srmclient
Maven modules. The packaging is triggered by activating the profiles
rpm and deb by using the -P option of Maven. The profiles are exclusive
and must not be activated at the same time. Like the old Ant targets,
the profiles allow the build number and local version strings to be
modified by overriding properties through the -D option of Maven.

Solaris packaging tools are moved to the FHS module too, I do however
not have a Solaris system for testing and thus I leave it to somebody
else to define the necessary Maven profile to invoke the packaging.

I removed all legacy packaging components and all Ant files. This
includes a couple of old spec files, including for dcap. Like for
the Solaris package, I hope somebody else can ressurect this within
Maven (or move the dcap client code out of the dCache repository and
into its own repo).

Finally, I moved the packaging related Maven modules into its
own top-level directory to separate them from the modules that
contain our source code.

Target: trunk
Require-notes: no
Require-book: no
Acked-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Patch: http://rb.dcache.org/r/5589/