If a user wants to change its password, but does not
 submit a valid form it still gets a 'Succesfully changed password'
 message.

Due to potential data loss during migrations
 with the use of `auto_now`, it is recommended
 to write create a custom auto-now-field.

Creating a new ThesisLink didn't save the `requested_by`
 field, causing trouble in for example the vet view
 for these specific objects.

Improve the templates using template tags.
 Further, wrapping the `content` block in the
 `container` div element.

Test if thesis is vetted/deleted and mail is sent in
the accepted/refused case.

Merge branch 'fix-thesis-vetting' of https://bitbucket.org/scipostdev/scipost_v1 into fix-thesis-vetting

Altered the message alert class and positioned it absolute to
 the body to have floating messages.

Add missing migrations

Migrations involve appending default values to model fields

Improvements submissions

Write test for bug from last commit.