Narrative:
As an editor of Wikidata-Lexeme I want to be able to add an additional statement to a Sense in order to describe it more thoroughly.

Acceptance Criteria:

• I can add an additional Statement to the Statement section of a Sense in the same way as on an Item, Property, Form or Lexeme
• The edit is stored persistently

Given: I am on a Lexeme with a Sense
When: I click "add statement"
Then: a statement box appears
And: I can enter a property and value
And: I can save the new statement

Personas to take into account:
Niels - Active editor on Wikidata
Alex - Data user in small startup

This story does not include adding multiple statements without reloading a page.