Log Message:
py-flask-flatpages: Update to 0.7.0.

Version 0.7.0
~~~~~~~~~~~~~

* Update to Markdown 3.0 with new extension loading syntax.
* Added `FLATPAGES_EXTENSION_CONFIGS` for configuring extensions
  specified by import string.
* Add support for loading pages from Flask instance folder
* Add a case insensitive loading option

Version 0.6.1
~~~~~~~~~~~~~

* Update dependencies to `Flask>=1.0` (as Flask 0.12.1 has known
  vulnerabilities).
* Pin `Markdown<=3.0` as the Markdown extension API has changed.