(tox) Moved everything test-related to /tests

Moved everything test-related from cmsplugin_filer_image/ to cmsplugin_filer_image/tests/.
(tox) Updated .gitignore
(tox) Updated tox.ini and test files
(tox) Updated dependencies in setup.py
Merge branch 'master_pbs' into tox

Conflicts:
	tox.ini
(tox) Fixed dependency version and tox build folder
(tox) Added sample urls.py for tests
Merge branch 'master_pbs' into tox

Conflicts:
	tox.ini
(tox) Added more flags to tox.ini
Merge branch 'master_pbs' into tox

Conflicts:
	.gitignore
Merge pull request #28 from pbs/tox

Integrated Tox