Add documentation on creating the database.

Review Request #6377 — Created Sept. 26, 2014 and submitted — Latest diff uploaded

Information

Review Board
release-2.0.x
c6b2b62...

Reviewers

This adds a section at the beginning of the "Creating a Review Board Site"
document which shows the steps for creating a new database and a user to access
it for both MySQL and PostgreSQL. For MySQL, this makes sure that it shows how
to turn on UTF-8 before doing anything.

Built HTML docs.