thomasgriffin/TGM-Plugin-Activation — pull request #213 by ctalkington (2014-08-14 01:31:52+00:00)
Title: encode urls passed to add_query_arg.

fixes issues with s3/cloudfront urls and install/activate links.

> .. Additional values provided are expected to be encoded appropriately
> with urlencode() or rawurlencode(). ...

http://developer.wordpress.org/reference/functions/add_query_arg/