[views/templates] provide a modal main template (closes #3274672)
The current NonTemplatableViewTemplate may seem to provide the desired
feature if a '__notemplate' is provided in the form, unfortunately,
it:
* wraps the view in a spurious div
* calls view.set_stream(), which has the effect of wiping any js/css
resource recorded until then by the view, leading to hard-to-track
missing resources symptoms
usr/lib/PY_VERSION/*-packages/cubicweb/devtools/
usr/lib/PY_VERSION/*-packages/cubicweb/skeleton/
usr/lib/PY_VERSION/*-packages/cubicweb/test
usr/lib/PY_VERSION/*-packages/cubicweb/entities/test
usr/lib/PY_VERSION/*-packages/cubicweb/ext/test
usr/lib/PY_VERSION/*-packages/cubicweb/server/test
usr/lib/PY_VERSION/*-packages/cubicweb/sobjects/test
usr/lib/PY_VERSION/*-packages/cubicweb/hooks/test
usr/lib/PY_VERSION/*-packages/cubicweb/web/test
usr/lib/PY_VERSION/*-packages/cubicweb/etwist/test