Make Web::Template::Mojo work

Looking for the template file always failed, due to a missing path
separator.

Templates named with the ".tm" extension weren't checked for.

Named parameters weren't passed along to the template, even though
a common idiom does use them (see eg/02-complex.tm in Template-Mojo).
Merge pull request #1 from softmoth/fix-mojo

Make Web::Template::Mojo work