Remove trailing whitespace that caused PHP "cannot modify header" error.
Implement basic CSV file parsing.
Fix bug where `EMI_Location::set_location_id` didn't actually set value.
Fix bug where `EMI_Location` object failed to set its own `location_id`.
Update UI to reference CSV import is an option, add a `<label>` to form.
Use WordPress's timezone string rather than a hard-coded value.
Detect if PHP will truncate `$_POST` superglobal and warn the user!
Multiple events can have the same name, so check dates as well.