Auto-update Jenkins build dependencies (#121)
Auto-update Jenkins build dependencies (#121)

* Add script to initialize system before CI build

The init_build.sh script updates versions of dependencies,
such as go language or Helm, when running on Jenkins build worker.
This allows a commit to upgrade version of dependencies and even
though the Jenkins worker image may have a different version of
the dependency preinstalled, the dependency will be upgraded to
match the version required by the commit being processed.

* Install glide in CI build if needed

If glide is not installed in the CI worker image, or if a different
version is installed than a version required by the commit being
processed by CI, install correct/matching version of Glide.

* Ask installed dependencies for versions

Rather than relying on a handshake with the Jenkins
image builder to inject the versions into version files.

* Move init_build to hack/jenkins

kubernetes-incubator/service-catalog,kubernetes-sigs/service-catalog,kubernetes-incubator/service-catalog,n3wscott/service-catalog,jboyd01/service-catalog,arschles/kubernetes-service-catalog,duglin/service-catalog,bmelville/service-catalog,MHBauer/service-catalog,jpeeler/service-catalog,staebler/service-catalog,kubernetes-sigs/service-catalog,martinmaly/service-catalog,kubernetes-sigs/service-catalog,kubernetes-sigs/service-catalog,bmelville/service-catalog,kibbles-n-bytes/service-catalog,jpeeler/service-catalog,n3wscott/service-catalog,MHBauer/service-catalog,jboyd01/service-catalog,krancour/service-catalog,pmorie/service-catalog,vaikas-google/service-catalog,kubernetes-incubator/service-catalog,pmorie/service-catalog,jboyd01/service-catalog,vaikas-google/service-catalog,arschles/kubernetes-service-catalog,bmelville/service-catalog,kubernetes-incubator/service-catalog,martinmaly/service-catalog,krancour/service-catalog,duglin/service-catalog,arschles/kubernetes-service-catalog,staebler/service-catalog,kibbles-n-bytes/service-catalog,MHBauer/service-catalog,n3wscott/service-catalog,kubernetes-incubator/service-catalog,staebler/service-catalog,jboyd01/service-catalog,kibbles-n-bytes/service-catalog,krancour/service-catalog,kubernetes-sigs/service-catalog,mdshuai/service-catalog,kibbles-n-bytes/service-catalog,jboyd01/service-catalog,pmorie/service-catalog,n3wscott/service-catalog,n3wscott/service-catalog,duglin/service-catalog,staebler/service-catalog,n3wscott/service-catalog,MHBauer/service-catalog,kubernetes-sigs/service-catalog,kibbles-n-bytes/service-catalog,jpeeler/service-catalog,kubernetes-incubator/service-catalog,MHBauer/service-catalog,martinmaly/service-catalog,jboyd01/service-catalog,duglin/service-catalog,staebler/service-catalog,mdshuai/service-catalog,mdshuai/service-catalog,kibbles-n-bytes/service-catalog,staebler/service-catalog,duglin/service-catalog,duglin/service-catalog,vaikas-google/service-catalog,bmelville/service-catalog,MHBauer/service-catalog