RHEL7 copr repo is in different location

Updated the doc to point users to a different URL for the RHEL
copr repo.
Temporary RHEL package install fixes

* python-ironicclient is missing from installed repos
* remove tripleo-selinux-keepalived.te
Use an element for python-futures workaround
Add network-gateway element to overcloud image builds
Add tripleo-image-elements element and use it in overcloud builds
Remove workaround to remove the ip address from eth1, it's happening automatically now
Add element for os-cloud-config so we can remove the req from the spec file
Remove unused discovery-dhcp element
Remove oslo-serialization from overcloud image builds and remove the now unused element
Add new answer file config params to instack-apply-config
Remove unused ceilometer-delorean element
Update cherry picks and $LKG for diskimage-builder
Merge pull request #67 from rwsu/rhel-packages

RHEL package install updates
Update README.md
Update README-packages.md
Add README-baremetal.md
package-installs-tripleo-image-elements should be under install.
package-installs-os-cloud-config should be under install.d
Add a timeout at the end of instack-virt-setup if the the instack vm never gets an IP address
Update README-packages.md