Update submodules.
Define namespace prefixes based upon configuration.
Add {% for ... %} ... {% endfor %} and basic object accessors.
Remove debugging output.
token_free(NULL) should be a no-op
Add an overarching 'environment' object into which templates are loaded.
Add 'include' tag.
Add 'escape' filter.
Add common logging and memory management.
Refactor filters, tags and blocks. Add rudimentary if/endif.
Add {% else %}
Add {% elsif <expr> %}
Add 'upcase' and 'downcase' filters.