The source-jar-generation maven plugin is to enable me to do mvn package and have the source jar instead of waiting for an official release.
The change to 1.4.0 was motivated by the update to Jackson 2.x which is major, and the version change of httpclient, to a lesser extent.
Updated the changelog and dependencies files to reflect the changes made until now.
Added source jar generation.
Changed version to 1.4.0-SNAPSHOT.