Restore list_children()

I accidentally deleted this method for #264, by simply hacking off too
much. :-/
Merge remote-tracking branch 'upstream/master'
Provide a link to the state-level regex repository
Working around a PHP bug

A function return value can't be used in a write context.
Move images into default templates directory
Rename jQuery Color file
Normalize case of true and false

All should be uppercase.
Resolve problem of duplicate calls to jQuery Color
Fix bug preventing structural data from loading

Per #264.
Update the introduction to include Maryland
Markdown formatting changes
Rewrite optional modules listing
Explain how to contribute
Change description of where to find out more
Update the DSN constant to support PDO

Per #253.
Replace the MDB2 connection with a PDO connection

Per #253.
Replace all MDB2 code with PDO code

Per #253.
Replace all MDB2 code with PDO code

Per #253.
Fix PDO::rowCount()

Per #253.
Replace all MDB2 code with PDO code

Per #253.