FIX redirecting to absolute path error

* was: POST and PUT redirecting to relative path on update
* caused: editing page like `page/2` redirects to `page/page/2`
* fixed: add leading slash
Add tests and fix typos
Merge branch 'FIX-absolute-path-redirect' of https://github.com/jangxyz/ecogwiki into jangxyz-FIX-absolute-path-redirect

Conflicts:
	tests/test_handlers.py
	views.py
Fix atom feed