small text change in dev docs

dev docs: note added

renamed tox env `rerecord` => `record`

typo in development docs

* add testing documentation ...

* add a sample mailman.cfg for testing

add env for fixture re-recording to tox.ini

reduced number of vcr cassette files used in current tests

modified vcrpy setting to use yaml instead of json; add more testing documentation (draft)

Some documentation cleanup; New testing section (draft)

Bump Copyright Years

- removed documentation build from repository ...

- removed an unused rst file
- removed some outdated development documentation

Merge trunk

* Added tox configuration and new test setup ...

* Modified some existing tests to not break when run independently from the standalone project.
* Added a test for the list metrics page.

Show held message details in a modal window. Contributed by Abhilash Raj (LP: 1004049).

Fix broken translation string on the login page. Contributed by Pranjal Yadav.

Fix small bug moderator/owner forms on list members page. Contributed by Pranjal Yadav (LP: 1308219).

fixed a rendering bug on login page

fixed 1308219 and merged trunk

save fixtures to postorius package

merge trunk

added vcrpy to some tests

Fixes #1004049

Added credits for Abhilash's contribution to news.rst

* URLs now contains the list-id instead of the fqdn_listname. Contributed by Abhilash Raj (LP: 1201150). ...

* Added dev_requirements.txt for installation of development dependencies.

moved some tests to vcrpy

Change fqdn_listname with RFC 2369 list-id in URLs

Fix wrong labels in metrics template. Contributed by Sumana Harihareswara (LP: 1409033).

Fix untranslatable template strings. Contributed by Sumana Harihareswara (LP: 1157947).

Fix adding the a list owner on list creation. Contributed by Aurélien Bompard (LP: 1175967).

Show error message in login view. Contributed by Aurélien Bompard.