update metadata generator for new specification

- digital signature no longer required (and now on different element)
- top-level ID attribute removed (was only required for signature)
- SAML 2.0 metadata namespace is now the default
- validUntil parameter echos expiry date of signing certificate
- SingleLogoutService no longer required
- ResponseLocation no longer required on AssertionConsumerService
- NameIDFormat section now required
- Organization section now required
update dependencies: Date::Parse required to extract cert expiry
add note to confirm module works with RealMe
bump version for release
update SP metadata in test config to new format
tests for accessors added/removed
v1.06

    - update metadata builder for changed spec (digital signature removed,
      various other parameters added and removed)
    - add note to confirm module works with RealMe