Cleanups and documentation.

tdt4140-gr1800/app.core/README.md

tdt4140-gr1800/app.core/doc/document-storage.md

tdt4140-gr1800/app.core/doc/document-storage.png

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

...ore/src/main/java/tdt4140/gr1800/app/core/GeoLocated.java

...re/src/main/java/tdt4140/gr1800/app/core/GeoLocation.java

...pp.core/src/main/java/tdt4140/gr1800/app/core/Tagged.java

.../app.core/src/main/java/tdt4140/gr1800/app/core/Tags.java

...rc/main/java/tdt4140/gr1800/app/core/TimedTaggedImpl.java

...a/tdt4140/gr1800/app/doc/AbstractDocumentStorageImpl.java

...c/main/java/tdt4140/gr1800/app/doc/IDocumentImporter.java

...c/main/java/tdt4140/gr1800/app/doc/IDocumentListener.java

...src/main/java/tdt4140/gr1800/app/doc/IDocumentLoader.java

.../src/main/java/tdt4140/gr1800/app/doc/IDocumentSaver.java

...rc/main/java/tdt4140/gr1800/app/doc/IDocumentStorage.java

...java/tdt4140/gr1800/app/doc/IDocumentStorageListener.java