More documentation.

tdt4140-gr1800/README.md

tdt4140-gr1800/app.core/README.md

tdt4140-gr1800/app.core/doc/db-persistence.md

tdt4140-gr1800/app.core/doc/db-persistence.png

tdt4140-gr1800/app.core/doc/domain-classes.png

tdt4140-gr1800/app.core/doc/domain-model.md

tdt4140-gr1800/app.core/doc/json-persistence-classes.png

tdt4140-gr1800/app.core/doc/json-persistence.md

tdt4140-gr1800/app.core/doc/location-based-storage.md

tdt4140-gr1800/app.core/doc/location-based-storage.png

tdt4140-gr1800/app.ui/README.md

tdt4140-gr1800/web.server/README.md