Rename closure-library to obvious-closure-library, so we can publish it on npmjs.org

Hello @dpup, 

Please review the following commits I made in branch 'nick-package'.

4e9d4cb2709d8aff7e62c88760ad7074b9850272 (2013-06-27 11:39:45 -0400)
Rename closure-library to obvious-closure-library, so we can publish it on npmjs.org


R=@dpup