Move in API documentation from old git repository.
Exclude generated RST and DOT files from git.
Improvements to documentation.
Name of acccess key parameter is now 'token'.
Add script to build Sphinx documentation.
Clean up documentation.
Rename AbstractObject.load_from_graph() to add_metadata().
By default, the attributes of an AbstractObject can only take a single value (i.e. the property is functional).
Both a Recording's source and an Annotation's tags can be multi-valued.
Fix typo.
Minor code tidy.
Be consistent with name when passing repository access key as a parameter.