Add task and utilities to dynamically generate Jenkins uber_build job

This commit adds a task that will erb an XML template that contains a Jenkins
job configuration, and then create that job on the jenkins server using the
jenkins_api_client library. The jenkins_api_client library will be added to the
top-level vendor library.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Add vendored jenkins_api_library

This commit adds the jenkins_api_library as a vendored library from
https://github.com/arangamani/jenkins_api_client. We'll use the API to
dynamically create jenkins jobs for our packaging.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
add erb template to create dynamic jenkins job
Add appropriate dependency to jenkins dynamic
Set current location when setting path in dynamic task
Merge branch 'dynamic_jobs' of github.com:MosesMendoza/packaging into melissa