More reliable method of extracting affiliations. Improve table presentation. Sticky form submit buttons. Use clientside validation for the form. Allow non-numerical identifiers for affiliations.

fixes #353

reword assignment stage update email
disable automatic withdrawal after assignment deadline

fixes #336

add assignment deadline extension button for edadmin/authors

fixes #335

prevent crashes when tex contents are empty

Allow none logic for PublicationAuthorsTable

optimize journal about page

related to #302

fixes #316

truly fixes #255
reimplementation of 8a7b2a8b

fixes #255

rename verbose name of approaches