TREFF: Update input names to better follow what they are

Also add two hidden fields to hold the lat/lon
TREFF: Set anonymous = true when we create an anonymous user
TREFF: Formatting
TREFF: Get the meeting id from a GET variable
TREFF: No need for global hooking since the form calls the function
TREFF: Add a placeholder for where we need to calculate the lat/lon of an address
TREFF: Create process.php