Fix files that are missing their final newline
Fix API version - v0.1 is current, v1 is from the old version scheme
In recent PopIt, 'organisation' is now spelled 'organization'
The collection names are all pluralized now
Rename the popit module to popit_api to avoid a name clash

Unfortunately, the name popit at the top level clashes with
popit-django, which is more widely used at the moment.  So,
rename the popit module to popit_api.
Update the README for the current popit-api
Replace literal tabs with 4 spaces and strip trailing whitespace
Don't import *, just import the exception we need
Update the "delete a deleted object" test for new API behaviour

At one point the PopIt API returned a 404 if you tried to DELETE
a non-existent object, but in the current version it'll return
204 No Content.  Update the test that checks for this case.
Stop slumber from appending slashes to URLs

This causes object deletion, for example, to fail since the URL
ends in an ID - PopIt interprets a trailing slash as part of the
ID.
The "comment" field of a link is now called "note" in the Popolo spec
Upgrade slumber and its dependencies

This seems to be required to get the tests to pass, and it's a good
idea to use up-to-date versions of these libraries anyway.