Bumped to 2.48.0

boto v2.48.0
============

:date: 2017/06/29

This release addresses a few S3 related bugs as well as a bug with the recent
endpoint heuristics feature.

Changes
-------
* Fix generate_url() AttributeError when using anonymous connections (:issue:`3734`, :sha:`83481807`)
* Use RegionInfo by default with heuristics (:issue:`3737`, :sha:`0a9b1140`)
* Allow specifying s3 host from boto config file. (:issue:`3738`, :sha:`dcfc7512`)


