PDF is binary

See merge request !316

Clarify some things about settings with some comments

See merge request !315

Display correct initial join date for consecutive committee memberships

Closes #278

See merge request !313

Warning that full-sized photos are not saved

Closes #275

See merge request !297

This typically resulted in incorrect dates for committee chairs
who had previously been member of the committee as nonchair

Fix warning in tests

See merge request !312

By properly closing the opened thabloid file

super()'s tearDownClass() should be called in the overridden method.

Test the Thaliapp API

See merge request !290

Add '[THALIA]' to subject of newsletters, as it should be :)

See merge request !311

Fix comparison of two possible NoneTypes

See merge request !310

Fix sitemap.xml

Closes #287

See merge request !308

Errors naar django errors

See merge request !309

Fix 500 error when trying to display showcased partner that is removed

See merge request !305

Prevent board memberships from ever expiring

Closes #283

See merge request !304

Report test coverage

See merge request !301

Order newsletter items

Closes #179

See merge request !298

Add message to the end of the newsletter regarding language change

Closes #182

See merge request !299

Make  sure that members cannot cancel or change pizza order when not allowed

Closes #271

See merge request !295

Improve exam upload form

Closes #269

See merge request !294

Fix #271

Translate Thalia logo images

See merge request !300