TiddlyWeb tool establishing package based hosting of Jinja2
templates in the tiddlywebplugins package space.

The templates are overridable with local templates in the
TiddlyWeb instance.

The tool provides a get_template method which takes a template
name or path. First the tiddlyweb.config['plugin_local_templates']
directory (defaulting to 'templates') is searched. Then the
tiddlywebplugins.templates package space is searched (looking
for the template as a pkg_resource).

This searching may not work for all packaging systems. This has
been tested with pip.