Added 2.3.0 changes

git-svn-id: https://svn.apache.org/repos/asf/ant/ivy/core/trunk@1441234 13f79535-47bb-0310-9956-ffa450edef68
FIX: NullPointerException when using httpclient and server doesn't return content-type header (IVY-1400) (thanks to Frederic Riviere)

git-svn-id: https://svn.apache.org/repos/asf/ant/ivy/core/trunk@1441235 13f79535-47bb-0310-9956-ffa450edef68