Change event messages

Changed structure to be inline with Symphony core. Added event messages as for 2.4 core
Extend EventMessages, and tidy codes up
Typo fix
missing comma
Even more events normalisation
Merge pull request #249 from embarknow/integration

Update Events to make use of `EventMessages`
missed a message ID
Merge pull request #251 from embarknow/integration

missed a message ID.

@brendo, as this is a minor fix, I just merged it.
Added delegate for a failed Member login attempt.
Corrected param description.
Fix delegate security issue.
Add delegate for a failed password reset.
Fix indentation, using tabs is standard here.
Removed unnecessary SQL queries when checking activation
Merge pull request #256 from g-wilson/integration

Removed unnecessary SQL queries when checking activation
Possbile resolution for #257
Update password filter needs the authentication field, not the activation field
Update event descriptions to be a little clearer
Make better use of EventMessages responses. Closes #250
Ensure valid email address before attempting any login logic. Closes #228