(SERVER-2034) Add -master back into version string
(SERVER-2034) Add -master back into version string

Some of the automated performance tests search for the latest build with
the word -master in the version string. This broke when -master was
removed from the version string between 5.0.1 and 5.1.0. This commit
adds it back in to get those tests working again.

puppetlabs/puppetserver,puppetlabs/puppetserver,puppetlabs/puppetserver,puppetlabs/puppet-server,puppetlabs/puppetserver,puppetlabs/puppet-server,puppetlabs/puppet-server