Provide a Validator Service

[Thomas Berezansky]

From the commit:

OpenSRF Validator Service

Add a new Validator service, and EmailAddress validators.

The service runs a chain of one or more validators, each one being fed the normalized output of the previous one.

The return from each validator should be a hash of valid (0 or 1), the new normalized output (the untouched input if invalid or nothing needed to be changed), and if invalid an error string. Optionally, a validator can also include an "additionals" hash of extra information to be included in the final response.

The complete list of validators included is:

OpenSRF::Application::Validator::Base
    The base validator. Always returns valid.
OpenSRF::Application::Validator::Invalid
    Always returns invalid for testing purposes.
OpenSRF::Application::Validator::EmailAddress::Regex
    Does a very basic regular expression check on email addresses.
OpenSRF::Application::Validator::EmailAddress::DNS
    Uses Net::DNS to look up the domain on an email address

http://git.evergreen-ils.org/?p=working/OpenSRF.git;a=shortlog;h=refs/heads/user/tsbere/opensrf_validator

[Dan Scott (denials)]

Tested out nicely - I added one further commit to add basic tests, bring the MANIFEST up to date, and note the new dependency in Build.PL, but those were minor. Pushed to master.

Thanks very much Thomas!