specs: Package release tags should start at 1

The RPM packaging guidelines say that the 'Release' tag starts
at 1 and is incremented whenever the package is changed but the
packaged version of the software remains the same.

Signed-off-by: Euan Harris <euan.harris@citrix.com>
Merge pull request #135 from euanh/build-improvements

specs: Package release tags should start at 1