Fix Fedora Puppet failure to use pip

In Fedora the pip command used by the packaged python-pip is
"pip-python" rather than "pip" due to a naming conflict. The
Puppet module tries to compensate, but we don't use the Fedora
package, so the command really is "pip" for us.

Adding symlink line to install_puppet.sh for Fedora to add the
pip-python command that Puppet is looking for.

Change-Id: I60a03fb6c27a18cd8a536080bcce1baaba965237
Add all images and increase usage of region-b

Only increase max-servers to 28 (enough for 1 of each of the four
images on all jenkins masters) to exercise them a little and let
us spot problems without a huge impact.

Change-Id: I1d27998eae1be2eb156f482ee6889e9d3ca74e05
Merge "Add all images and increase usage of region-b"
Merge "Fix Fedora Puppet failure to use pip"