Set up a system for using labels

[Daniel-Mietchen]

Right now, https://github.com/okfn/opendataday/labels are used very sparsely, which makes it difficult to keep track of issues.

Some suggestions:

• website
• documentation
• events
• grants
• outreach
• locations
• topics
• translations

Perhaps we could also have a label for each year.

[morchickit]

Done!