Remove @build_date and make it a @build variable

@build_date was a temporary workaround until we established a true instance
variable for the @build object. This commit replaces @build_date with
@build.build_date wherever we use it. This will also be important because we'll
use it when we trigger the dynamically created jobs with jenkins.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Remove temporary staging artifacts
Add a fail_on_dirty_source utility method

We'll use this in both jenkins.rake and jenkins_dynamic.rake.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Pull library requirement out into a utility method

We require and fail with a message all over the place, so let's abstract into a
utility method.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Add job triggering to jenkins_dynamic.rake

Previously, jenkins dynamic could create the jobs, but not trigger them. This
commit updates the dynamic job creation to also trigger the execution of the
job first job after it has been created. Unfortunately, this uses a lot of the
same logic that jenkins.rake does. Ideally we would be able to get rid of all
of this duplication, and we will. Just not right now.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Update packaging.xml.erb to quote the workspace/params file path

And always build unless we failed
Job creation order may actually be important. Oh jenkins..

Also remove an extra newline in the tmeplate