docs(troubleshooting): added instructions on manually updating CoreOS
ref(troubleshooting): move coreos upgrade docs
style(docs): style cleanup
docs(upgrading): mention CoreOS minimum requirement
fix(builder): force newline
feat(provision-rackspace): added optional parameter to specify environment
docs(installing_deis): added reference to optional environment parameter
chore(provision-rackspace): bumped coreos image version
fix(deisctl): make restart call start and stop properly
ref(deisctl): purge update engine logic
fix(router): only add x-forwarded-proto on https

Prior to 1f74eeb, sending decrypted https traffic to port 80 worked fine
in the case that there was an https endpoint/load balancer in front of
the cluster. In this example, the addition of X-Forwarded-Proto changes
the forwarded protocol from https to http. Making the prototype only
available when an SSL certificate and key is installed fixes this.
Merge pull request #2404 from bacongobbler/force-newline

fix(builder): force newline
Merge pull request #2397 from bacongobbler/patch-7

docs(troubleshooting): added instructions on manually updating CoreOS
Merge pull request #2419 from gabrtv/remove-updater

ref(deisctl): purge update engine logic
Merge pull request #2409 from Imdsm/provision-rackspace

feat(provision-rackspace): added optional parameter to specify environment
fix(*): Corrected required cores version
chore(contrib/rackspace): bump CoreOS to 490.0.0
Merge pull request #2423 from carmstrong/rackspace_490

chore(contrib/rackspace): bump CoreOS to 490.0.0
Merge pull request #2422 from johanneswuerbach/required-coreos

fix(*): Corrected required cores version
Merge pull request #2383 from bacongobbler/2381-x-forwarded-proto

fix(router): only add x-forwarded-proto on https