fixed some of the schema

Did most of Atsu's requests except still need to:
-"Most of these should have "not null" constraints"
-"represent the completed status with just a single completed_time field that's allowed to be null"
-"arrays in db"
Metrics/LineLength: Line is too long. [187/130]<br>Style/SpaceInsideHashLiteralBraces: Space inside { missing.<br>Style/SpaceInsideHashLiteralBraces: Space inside } missing.