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was causing a fatal error
Add a privacy filter
Remove old privacy query parts
Fix garbled sql for feed media

Use a similar syntax to the privacy filter.  Using the two dissimilar methods was causing errors in the SQL (cross joins, etc).
Add a method to get an array of feed IDs for a user

This can be helpful for programmatic reasons
Optimize the privacy filter
Make the privacy filter easier to test

Pass the user object in the constructor
Fix timezone differences

Dates were being stored as a different timezone, so use the MYSQL internal date functions.
Add a method to set the current user
Add tests for privacy
Remove the `datecreated` constraint and show all media

The filter is still expected by the application template logic for determining the current filter type, etc.
Merge pull request #215 from mfairchild365/private-media

Fix Private media