Fix for issue #79

Don’t leave a single unchecked malloc
Support for absolute paths in bundle-based repositories.

(Extra robustness for PR #78)

For consistency with path-based repositories, absolute partial paths
{{> /partial }} looks at the root of the bundle.
Tests for hierarchy of templates in bundle-based repositories.

(Extra robustness for PR #78)
Documentation for hierarchy of templates in bundle-based repositories

(Extra robustness for PR #78)
Merge branch 'master' into Visitors