feature/IN-489: Update Passport SAML package to handle customised Namespace qualifiers.

Fix to make the validate Response function independent of the Namesapce qualifiers. The fix involves using a regex to extract the hash keys in the SAMsapce qualifiers. The fix involves using a regex to extract the hash keys in the SAML response. This makes it independent of the customized namespace qualifiers.
feature/IN-489: Refactoring to remove unused code.
feature/IN-489: Removed comment statements.
feature/IN-489: Optionally add or skip the appending of SAML request parameter in the authentication url
feature/IN-489 : Added option to include the SPID in the auth request url

Like RelayState this is a custom parameter SPID which needs to be added to some tenants to make their authentication server accept requests from us.
Adding back a comment which was accidentally removed
Merge pull request #2 from kaybus/feature/IN-489

Feature/in 489: Update Passport SAML package to handle customised Namespace qualifiers