Common rules checkbox

[dreh23]

This feature is described in 3.1. of the reference document. As discussed in a call it has following properties:

1. A subfolder in backend/resources with text files
2. These a read on project creation/compile time and injected as checkbox list into the frontend and saved to the database
3. On Report creation a table is rendered with the text and values from the database

[hemarkus]

1. store obligation text in couchdb
2. admin interface for creating, updating obligation text
3. store fulfilled relation
4. store username, date, hash of obligation text
5. change term to e.g. project level obligation