code cleaning and set defaults:

   * original FB does not support two-stage async auth.
   Now it supports, we revert to SNSAPI default.
   See 'snstype.AuthInfo' for the defaults.
resolved
Merge branch 'master' of github.com:fqj1994/snsapi into dev
fix the UT of SNSBase.new_channel
change to rel tmp dir
Merge remote-tracking branch 'upstream/dev'
(facebook) add photo link to facebook feed