Fix Jean-François' name
Fix filtering with accented letters

Do not convert the search string to Upper Case because SQL is case sensitive for non-ASCII characters.  The `LIKE` SQL operator is case insensitive for ASCII characters.
Fix a typo in a constant name
Use arrays of email addresses instead on strings
More "functional" code
Notify all COMB members of all registrations

Notify all COMB members of all registrations.  Do not send double notifications to Jean-François, he is in COMB mailing list.
Change the registration deadline to 10 avril