Hard-coded "r1" in build scripts and instructions

[Bruce Jones]

The build and build documentation include an "r1" in the pathnames of the directories. It's been two years since r1, and I don't think we need it. If we want to include a release distinguishing directory, it should be parameterized across releases. Or just dropped.

[Ghada Khalil (gkhalil)]

Marking as Low priority - assuming there is no negative impact. Would be nice to fix, but should not hold up the release.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/745651

[Susendra Selvaraj (sselvar2)]

Just dropped Hardcoded 'r1', layered build is working fine.
Patch uploaded for build scripts: https://review.opendev.org/#/c/745651/

Same changes shall be propagated to .rst files for doc changes.

[Susendra Selvaraj (sselvar2)]

There is patch from Saul for the same: https://review.opendev.org/#/c/687400/
This removes both the r1 and the pike portion of the download path name.
This takes some coordination with the build team possibly due to changes required in Jenkins.
This will be discussed in Build Team Meeting on Tuesday.

[OpenStack Infra (hudson-openstack)]

Change abandoned by Susendra Selvaraj (<email address hidden>) on branch: master
Review: https://review.opendev.org/745651
Reason: abandoned in favor of Saul's similar review.

[Susendra Selvaraj (sselvar2)]

        - Scott expects this to require 1-2 days effort
        - TBD on when this work can be done.

[M Camp (mcamp859)]

Changing LP status to Fix Released since the associated review has merged:
https://review.opendev.org/762761