Fixed issues related to http client v2.5

@adamedx  @NimishaS  @kaustubh-d 

I've fixed issues related to new httpclient(v2.5). 
Also tested and it works fine on both httpclient v2.4 and v.25 .
httpclient 2.4 had 'SSPIEnabled || GSSAPIEnabled' so it might be good to leave both in place. 
note that between 2.4 and 2.5 #challenge method has changed, please make sure we test both versions.