Finish API documentation

[acka47]

There is some information still missing in the API documentation:

• Which fields do exist/can be queried?
• How is the coverage of a field regarding the whole dataset?
• Example queries (as templates for building your own query)

I suggest the following:

• On the blog, write a longer tutorial with example queries and screenshots.
• In the API documentation, describe in a short way how you can use the context/GND ontology and example entries plus the Lucene query language to build your queries. Link to the blog post for details.
• I am not sure about the documentation by annotating an example. We might use it as basis for the examples in the blog post or even add a person entry in the documentation. I will see what fits best when we move along.

@fsteeg, I noticed that the GND API documentation looks different than the other two (resources, organisations), especially the first two paragraphs differ. I think this should be consistent but can't say which approach is the best...

[acka47]

By now, we added two blog posts on the topic (http://blog.lobid.org/tags/lobid-gnd) and linked them at lobid-gnd (but not in the API documentation). Closing.