Passing ?limit=0 to the blueprints/list, blueprints/changes,
projects/list, modules/list should always return the total possible
results, not 0.
Also move the composer-cli test_diff to the end so that it will work
consistently. Do this by naming it test_z_diff.
These depend on there being a freshly installed lorax-composer API
server running, if there is no /run/weldr/api.socket they will be
skipped.
(cherry picked from commit 7700ae3135)
