Add tests for RPM requirements

Add logic to the existing RPM verify jobs that checks the requirements of an RPM, likely against a "master copy" of what we expect.

Requirements for a package where the SRPM was built into a noarch RPM on the CentOS CBS (baseline):

$ rpm -qp opendaylight-8.0.0-0.1.20171125rel2049.el7.noarch.rpm --requires
/bin/bash
/bin/sh
/bin/sh
/bin/sh
/usr/bin/env
java >= 1:1.8.0
rpmlib(CompressedFileNames) <= 3.0.4-1
rpmlib(FileDigests) <= 4.6.0-1
rpmlib(PartialHardlinkSets) <= 4.0.4-1
rpmlib(PayloadFilesHavePrefix) <= 4.0-1
shadow-utils
rpmlib(PayloadIsXz) <= 5.2-1

Requirements for a noarch RPM package built on ODL infra (not properly isolated, see INTPAK-10):

$ rpm -qp opendaylight-8.0.0-0.1.20171129snap1008.el7.noarch.rpm -R
/bin/bash
/bin/sh
/bin/sh
/bin/sh
/usr/bin/env
java >= 1:1.8.0
mono(System) = 2.0.0.0
mono(System.Management) = 2.0.0.0
mono(System.ServiceProcess) = 2.0.0.0
mono(System.Xml) = 2.0.0.0
mono(mscorlib) = 2.0.0.0
osgi(com.typesafe.sslconfig)
osgi(org.apache.myfaces.core.impl)
osgi(org.eclipse.persistence.core)
rpmlib(CompressedFileNames) <= 3.0.4-1
rpmlib(FileDigests) <= 4.6.0-1
rpmlib(PartialHardlinkSets) <= 4.0.4-1
rpmlib(PayloadFilesHavePrefix) <= 4.0-1
shadow-utils
rpmlib(PayloadIsXz) <= 5.2-1