feedback: raise warning if message cannot be sent

[GoogleCodeExporter]

When a feedback message is submitted through the data portal, it gets sent
to the registered contacts automatically, and both the submitter and
portal@gbif.org receive a copy of the message. If, however, the registered
contact email is invalid or missing completely, the message is not sent out
without any warning raised. What would be needed in this case is

- minimum: a warning message to portal@gbif.org that a submitted feedback
message could not be delivered

- possibly: a confirmation to the submitter recognising the sent feedback,
but informing of the fact that it could not yet be delivered because the
relevant contact has to be identified, and that this is in progress

- possibly: an entry of the feedback message into the log file area
instead, so that the content is not lost; this would need further thought,
as it might encourage spamming

Related item: it is possible to register data sources (and even providers)
without any contact email, e.g. by providing a text entry like "-" in the
relevant field. This should be prevented as far as possible and might need
an additional test during indexing for well-formedness of email addresses.

Original issue reported on code.google.com by josecua...@gmail.com on 31 Jul 2009 at 12:37

[GoogleCodeExporter]

Not registered users now receive a "you need to verify your email address" 
screen once they submit a feedback 
through the data portal. This informs them that the feedback email has not been 
sent yet , but that once they 
verify their email address, the email will be sent.

Original comment by josecua...@gmail.com on 22 Sep 2009 at 2:37