[packaging] Fix rpm rc versioning

Currently if a tag is formatted in the standard RC format for PL, e.g. appended with '-rcX', the rpm versioning will create a file with an extra '.' in it between version and release, e.g. 'puppetdb-1.1.0.-0.1rc1.el5.src.rpm'. This commit chops the dot from rpm.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Add override to rpm builds for building RCs

Currently, rpm acceptance packaging fails because the automation in the
yum.puppetlabs.com repo checks to ensure an RC version isn't getting shipped
into production unless we pass an OVERRIDE flag. For puppetdb's purposes, this
is what we want, so this patch adds the OVERRIDE flag.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Merge pull request #398 from MosesMendoza/maint/master/fix_rc_rpm_version

[packaging] Fix rpm rc versioning