Merge branches/slinkp-zopectl-exitcode-143813: Fixes bug 143813, zopectl should exit non-zero if child processes fail.

Second of three tests. Calling ViewPageTemplateFile's without any arguments worked so far. The version in zope.app.pagetemplate always requires one to pass in the view as an argument. Examples in the wild are found in plone.app.portlets.

Added a test for the first of three problems found in real life applications with the ViewPageTemplateFile

'unrestrictedTraverse' (apparent NameError).

by the GenericSetup community)

attribute names for content_type text/html and text/xml

of the environ)
(This patch landed first on the 2.11 branch (by TS))

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