Issue #303: Updated hadoop-* dependency versions for -hadoop2 to 2.2.0

In order to get the Scoobi WordCount example working on a CDH5-beta1 cluster,
I've changed the hadoop-* dependency versions from 2.1.0.2.0.5.0-67 to 2.2.0
and removed the dependency on the hortonworks repository at the same time.

WARNING: I have no idea how this will affect Hadoop distributions based on APIs released before 2.2.0, e.g. CDH4. (See Issue #300) However, 2.2.0 is the first GA release of Hadoop 2, so I guess there needs to be a decision whether you want to support pre-GA releases going forward. Over to you guys... :)