Update legal-guidelines.html

- Court order or a search warrant required before we’ll turn over any information relating to a specific post or comment.
- Requests must identify the site’s .wordpress.com URL.
- Civil requests must identify the specific information (as listed in our guidelines) sought. Otherwise, we will provide the user email address and date/time stamped IP address. 
- Separate sections for requests from government agencies/law enforcement and requests in civil cases.
- Added a “requests for takedown of other content” section that touches on our position regarding freedom of speech.