Rename project to clj-photo-memories

Make the project generic, so that it can connect in the future to
other APIs (eg. Trovebox).
Pass options in a service-agnostic way
Allow passing parameters to nose2 in run-tests.sh
Allow the user to select a service from the command-line
Better error message for wrong command-line arguments
Rough, naive implementation of a Trovebox client
Make HTML template generic and adapt to Trovebox

* Change the data passed back to the main program, as it had
  Flickr-specific fields.
* Make the HTML template use the new service-agnostic fields,
  which should work for all services.
* Request a 500x300 thumbnail from Trovebox so we keep the same
  thumbnail sizes in the HTML mail as for Flickr.
Ignore .nrepl-port
Adapt the Python functional tests so they work with Trovebox
Remove blank line (flake8 <- happy)
Don't consider /photos/list.json part of the base URL
HTML-escape photo descriptions

It's a pity that we'll lose links and such in Flickr photo
description links, but that's better than having XSS issues :-(
Update README to add the Trovebox support
Add Trovebox mock API server example images locally
Make returned photo info objects more generic

Now maps representing the info for a given photo always have the
same keys: :id, :title, :description, :page-url and :thumbnail-url.
Add unit tests for Trovebox
Clean up the mail template title a bit