DOC-1281: Puppet Server gems, puppetserver_vs_passenger

Some edits to gems and puppetserver_vs_passenger pages.
Merge pull request #300 from waynr/maint

(MAINT) Ensure gem subcommand tests honor GEM_SOURCE
(MAINT) Update developer docs re: running from source
(MAINT) Fix typos, simplify git submodule init for quickstart
(MAINT) Add some notes about debugging / ruby
Merge pull request #302 from cprice404/maint/master/update-dev-docs

(MAINT) Update developer docs re: running from source
Merge pull request #291 from jbondpdx/stable

DOC-1281: Puppet Server gems, puppetserver_vs_passenger
(WIP) Add lein-ezbake configuration.