define away Curl_ntlm_sspi_cleanup() when no windows SSPI build
Added the output message length as a parameter to both Curl_ntlm_create_type1_message() and Curl_ntlm_create_type3_message() for use by future functions that require it. Updated curl_ntlm.c to cater for the extra parameter on these two functions.
First: File curl_ntlm.h renamed curl_ntlm_msgs.h File curl_ntlm.c renamed curl_ntlm_msgs.c Afterwards: File http_ntlm.c renamed curl_ntlm.c File http_ntlm.h renamed curl_ntlm.h