PodTemplates should be optionally named

[iocanel]

The next release kubernetes-plugin will allow the user to name the build pod, based on the name set on the PodTemplate (currently are named kubernetes-xxx-yyy-zzz which is meaningless).

So it would be great if we were able to optionally pass a name.

Since for the biggest part we are composing PodTemplates I am not sure if it makes sense to use naming by type (e.g. maven, go, nodejs) though this could possibly be a default value.

An other approach would be to name templates in the same manner as we label them (by job name and build number). This would allows to easily correlate a build pod with a specific jenkins build. For example the pod would be named something like myproject-12-xxx-yyy-zzz.