Adds Finnish translations file
Merge pull request #55 from juho-jaakkola/finnish_translations

Adds Finnish translations file
Fixes deprecated use of getEntitiesFromRelationship() method
Merge pull request #58 from juho-jaakkola/relationships

Fixes deprecated use of getEntitiesFromRelationship() method
Register object classes on plugin activation and unregister them on deactivation

Classes left behind in the database after plugin deactivation were giving a notice
(e.g. "Class 'Event' was not found").
Adds .gitignore that ignores all files beginning with a dot
Refactoring for the event editing form

- Splits the form into multiple smaller view
- Gets rid of the HTML tables
- Separates PHP and HTML code a bit