This whole pull request is essentially a revert of 577e2386 and #11

Update nokogiri dependency >= 1.5

This brings OmniAuth-CAS more in line with other strategies like the
built-in Developer strategy, OmniAuth-Shibboleth, OmniAuth-SSO-Cookie,
etc.

Following http://guides.rubygems.org/patterns/

A previous update forcing only Nokogiri 1.6 breaks several
applications.  Since Nokogiri 1.5 still works just fine I
modified the dependency to be >= 1.6 which accounts for
Nokogiri 1.6 as well.

Support JASIG style extra attributes

Upgrading nokogiri dependency to ~> 1.6

Fix typo that caused CAS server port to be ignored

Change CAS spec a bit so that it exercises that
part of the configuration

For instance: https://mycompany.com/stuff/cas

The `url` is then automatically parsed out into the required `host`, `port`, and `ssl` properties.

This reverts commit 4fee900d.

Can't have Travis test 1.9.2 if we are declaring 1.9.3...

Revert "Revert "Updated .rvmrc file to use Ruby 1.9.3""

This reverts commit 053db9d4.

This reverts commit 6eff62b6.

Can't have Travis test 1.9.2 if we are declaring 1.9.3...

I've been using this in production long enough without issue that it is time to declare 1.0

If this is needed, I'll gladly accept a Pull Request.