Implement improvements/updates to CH-LOD

[kgrons]

This Issue will serve as tracking for our progress related to establishing procedures to update CH-LOD regularly.

Summary of update activity since initial release (June 2017):

• Added statements to existing IDs. If IDs already exist, @robertmhudson aligns them with external authorities, updates biographical info, fixes typos, etc.
• We have not added new IDs (e.g., works, names, events, instruments), records for events that have taken place since June 2017, or information on events prior to June 2017 that were not part of the original release. These events do appear on the Performance History Search (PHS), which is updated on a weekly basis.

We are actively working on the following tasks:

• Build and release improved CH-LOD versioning information/documentation when updates are made (when new dataset replaces old dataset).

• Improvements to the data model, including: assign genre at the event level; clearer indication of performer's role on each specific event.

• Build automated data pipeline to update CH-LOD on a weekly basis.

• Update README to increase clarity around project history and progress.

We will provide updates in this Issue, and update the README with announcements. Questions? Check out our contribution instructions under Get Involved.