Update master for stable/stein

Add file to the reno documentation build to show release notes for
stable/stein.

Use pbr instruction to increment the minor version number
automatically so that master versions are higher than the versions on
stable/stein.

Change-Id: I1b79f8a70ae21003eb9aaf3dea618356c11c2d25
Sem-Ver: feature
2 files changed