upgrade to HttpClient 4.0.3

from http://hc.apache.org/news.html

4.0.1: This is a bug fix release that addresses a number of issues discovered since the previous stable release. None of the fixed bugs is considered critical. Most notably this release eliminates dependency on JCIP annotations. This release is also expected to improve performance by 5 to 10% due to elimination of unnecessary Log object lookups by short-lived components.
4.0.2: This is a maintenance release that fixes a number of bugs found since 4.0.1
4.0.3: This is an emergency release fixing a critical regression in the SSL connection management code.