Fixed SpnegoWebflowConfigurer to use the evaluateClientRequest as documented

[miller79]

Changes include the following:

• Added conditional logic when mixedModeAuthentication is false to use
  startSpnegoAuthenticate flow. Otherwise it will use
  evaluateClientRequest.
• Modified createEvaluateSpnegoClientAction to be equivlent to the other
  Spnego actions on failure which is
  CasWebflowConstants.STATE_ID_VIEW_LOGIN_FORM

Since this change fixes the documentation listed out here, this change re-enables the functionality which may cause unexpected results to those using the defaults. Some of those properties are the following:

• cas.authn.spnego.hostNameClientActionStrategy
• cas.authn.spnego.hostNamePatternString
• cas.authn.spnego.mixedModeAuthentication
• cas.authn.spnego.ipsToCheckPattern

I have done my best to ensure as few changes are affected as possible.

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[mmoayyed]

Thank you. Just in case, you may want to post the same patch to the 5.3.x branch as well specially if you wish to use this fix in the next 5.3 patch release.