Publish community recognition guidelines from the PostgreSQL Core Committee.

Publish community recognition guidelines from the PostgreSQL Core Committee.

Publish the community recognition guidelines developed by the PostgreSQL Core
Committee from a navigation off of the "Community" section.  Add URLs from
several other pages on the PostgreSQL website in order to access the guidelines:

  * Donate
  * Events
  * User Groups

Additionally, this patch updates the contact email address for donation questions
to the PostgreSQL Funds Group.