orgtrello--compute-url
Let the computation take place
'Oops I did it again' driven development.
formatting
Extract tests into their own arborescence
Makefile added with one target - run the tests

tony@dagobah(0,10,) 16:47:55 ~/repo/perso/org-trello (master) $ make test
emacs --no-init-file -batch \
                -l ert \
                -l ./orgtrello-tests.el \
                -f ert-run-tests-batch-and-exit
Loading 00debian-vars...
Loading /etc/emacs/site-start.d/20apel.el (source)...
Loading /etc/emacs/site-start.d/50autoconf.el (source)...
Loading /etc/emacs/site-start.d/50dictionaries-common.el (source)...
Loading debian-ispell...
Loading /var/cache/dictionaries-common/emacsen-ispell-default.el (source)...
Loading /var/cache/dictionaries-common/emacsen-ispell-dicts.el (source)...
Loading /etc/emacs/site-start.d/50ess.el (source)...
Loading /etc/emacs/site-start.d/50flim.el (source)...
Loading /etc/emacs/site-start.d/50slime.el (source)...
Loading /usr/share/emacs24/site-lisp/slime/slime-autoloads.elc...
Loading /etc/emacs/site-start.d/50w3m-el.el (source)...
Loading /home/tony/.trello/config.el (source)...
Running 17 tests (2013-06-29 16:47:57+0200)
   passed   1/17  testing-add-card
   passed   2/17  testing-add-checklist
   passed   3/17  testing-add-list
   passed   4/17  testing-add-tasks
   passed   5/17  testing-check-or-uncheck-states
   passed   6/17  testing-get-board
   passed   7/17  testing-get-boards
   passed   8/17  testing-get-card
   passed   9/17  testing-get-cards
   passed  10/17  testing-get-checklist
   passed  11/17  testing-get-checklists
   passed  12/17  testing-get-list
   passed  13/17  testing-get-lists
   passed  14/17  testing-make-hash
   passed  15/17  testing-move-card
   passed  16/17  testing-orgtrello--compute-method
   passed  17/17  testing-orgtrello--compute-url

Ran 17 tests, 17 results as expected (2013-06-29 16:47:57+0200)