migrate fragmented content from wordpress and read the docs to the homepage

[yochannah]

The homepage should be the source of truth for many things it is currently not, e.g.:

• [ ] Events - currently at https://intermineorg.wordpress.com/events/, could be at intermine.org/events
• [x] privacy policy - currently at https://intermine.readthedocs.io/en/latest/about/privacy-policy/, could be at intermine.org/privacy-policy
• [x] citations - migrate any missing content from https://intermineorg.wordpress.com/cite/ to http://intermine.org/publications/#citing-us - it might be we can just remove the wordpress content and link to the already-present page on intermine.org in this case
• [ ] linking in to intermines. currently this is on the blog, but it should probably be somewhere else - perhaps the intermine technical docs or user docs.