added Servlet 3 dependency

Importing this template application in Eclipse shows error as the snoop.jsp depends on the Servlet API. It will improve user first time experience.
Modified directions so that manually create repo file will be updated by Puppet module when run
nsupdate_plugin: Exception logging now includes error output from nsupdate command

Bug 1089697
Bugzilla link https://bugzilla.redhat.com/show_bug.cgi?id=1089697
When troubleshooting DNS record addition/removal errors, it is helpful to have the error output from the nsupdate command. Specifically in scenarios where record changes only fail <1% of the time.
Follow rc convention and use Rails.logger to avoid large amounts of text in the exception string
Split duplicate code into seperate method
Pass dns action for logger as a string rather than a boolean
system arch guide docs - update gear directories
Make READMEs in template repos more obvious

https://trello.com/c/dKJfwLdh - origin_cartridge_170

Also, remove unnecessary .gitkeep files and replace duplicated
'ruby/versions/{1.8,1.9}/template/.openshift/*' files with
directory symlink to 'ruby/versions/shared/template/.openshift/'.
Merge pull request #5451 from VojtechVitek/improve_template_repo_readmes

Merged by openshift-bot
Change GroupOverride.empty? so group overrides with 1 component is not considered empty.
Change logic that splits group overrides up if their component don't belong to the same platform.
Automatic commit of package [rubygem-openshift-origin-node] release [1.25.5-1].
Automatic commit of package [openshift-origin-cartridge-jbosseap] release [2.18.2-1].
Automatic commit of package [openshift-origin-cartridge-jbossews] release [1.24.2-1].
Automatic commit of package [openshift-origin-cartridge-postgresql] release [1.25.2-1].
Automatic commit of package [openshift-origin-cartridge-jenkins] release [1.22.2-1].
Automatic commit of package [openshift-origin-cartridge-mock] release [1.20.2-1].
Automatic commit of package [openshift-origin-cartridge-php] release [1.25.2-1].
Automatic commit of package [openshift-origin-cartridge-python] release [1.25.2-1].
Automatic commit of package [openshift-origin-cartridge-jbossas] release [1.25.2-1].
Automatic commit of package [openshift-origin-cartridge-diy] release [1.23.2-1].