decrease column size for gist_access_id.

--HG--
branch : beta
fix syntax error for py <2.7

--HG--
branch : beta
extra : histedit_source : 9ae4454fb9390b45928061c28ee9f00983be9f5a%2C0068c2ac55cf81983dced142e0c53d2cd83161e8
Use unittest2 for testing

--HG--
branch : beta
extra : amend_source : 09beb01a58d5427ec7ae11d068878e1247a780bb
extra : histedit_source : b0a1962ac41160e260a48e5553516084940a7d6c
added tests for raw gists

--HG--
branch : beta
extra : histedit_source : aa6314117ff7d9536dacb3163cff9d11e5fd6321