Accept 'GSSAPI' in place of 'Negotiate' in --proxy-auth=
Accept 'GSSAPI' in place of 'Negotiate' in --proxy-auth=

Signed-off-by: David Woodhouse <b460d66aaf00c296a3db1c1d9eeafc081d5f7d70@intel.com>

mtmiller/openconnect,chadcatlett/openconnect,lins05/openconnect,neshema/openconnect,don-johnny/openconnect,brandt/openconnect,don-johnny/openconnect,lins05/openconnect,mtmiller/openconnect,matlockx/openconnect,brandt/openconnect,mveplus/openconnect-client,atyndall/openconnect,don-johnny/openconnect,neshema/openconnect,mtmiller/openconnect,liiir1985/openconnect,nmav/openconnect-mine,lins05/openconnect,liiir1985/openconnect,neshema/openconnect,liiir1985/openconnect,mtmiller/openconnect,cernekee/openconnect,atyndall/openconnect,lins05/openconnect,mveplus/openconnect-client,atyndall/openconnect,nmav/openconnect-mine,mveplus/openconnect-client,atyndall/openconnect,cernekee/openconnect,matlockx/openconnect,mveplus/openconnect-client,neshema/openconnect,matlockx/openconnect,brandt/openconnect,matlockx/openconnect,cernekee/openconnect,nmav/openconnect-mine,nmav/openconnect-mine,brandt/openconnect,cernekee/openconnect,chadcatlett/openconnect,chadcatlett/openconnect,don-johnny/openconnect,liiir1985/openconnect,chadcatlett/openconnect