Update to latest pbr

This commit moves switches tempest from the d2to1 version of pbr and
move to the latest version of pbr. However, there is a bug with
build_spinx so it doesn't work with a doc version set so that section
is removed from the doc conf.py.

Change-Id: I4fe14eb2b2e81132f8fa99936a031176b38c437b
Updated from global requirements

Change-Id: I2cc2769b89bd040064408faea30c448350fa5f00
Merge "Update to latest pbr"
Merge "Updated from global requirements"