This now allows for a more organized template structure. All templates
can now be accessed via "parent/child" paths, and are templated atop
the layouts/*.html files.

The layout files themselves are modular and can be included in each
other. The only caveat is layout/*.html NEED to define their own
template names like so:

{{ define "base" }}

The other page templates do not (and musn't) define their own template.

This reverts commit 4d8e06b62e423f07df5623af237973e9a4384b7a.