Remove hst:language in hst:template

I had a chance to look into the cnd and found that hst:language in hst:template did not make sense.
We have thought of templates as servlet dispatching template pages, so templates are just resolved and processed via servlets, not via internal scripting engine.
I have thought of script engines for components, not for templates.
So, it would make more sense to have hst:language for hst:abstractcomponent, instead of hst:template.
However, we don't have any requirements for scripting components yet, so I don't have any strong reason to have it now.

Anyway, I think we need to remove hst:language in hst:template.