Bugfix template selection

[snototter]

During initialization of DocumentPage instances, a bug caused rmrl to always render the template of the notebook's last page. The bugfix is trivial since this was only a mix-up (max instead of min).

For more context (if needed) - consider the inline documentation prior to the culprit line:

rmrl/rmrl/document.py

Lines 60 to 64 in 89b5cc3

	# I have encountered an issue with some PDF files, where the
	# rM won't save the page template for later pages. In this
	# case, just take the last-available page template, which
	# is usually 'Blank'.
	template_name = template_names[max(self.num, len(template_names) - 1)]

In such cases, len(template_names) would be less than self.num. Access with max would then raise an IndexError.
For all other exports (where self.num is always less than len(template_names)), this line will always select the last entry within template_names.