Make hadoop-lzo build cleanly against hadoop 2, and test cleanly against hadoop 1 and hadoop 2.

- Removed the hadoop jar that was checked in.
- Upgraded the hadoop dependencies to 2.
- Removed unused imports.
- Introduced a compatibility util that handles the relevant API incompatibilities.
- Added test as a dependency to package.
Used TaskID.forName() to avoid the constructor discrepancy (per Raghu).
Merge remote-tracking branch 'upstream/master' into sjlee-hadoop-2
Fixed (hopefully) the travis ci.
Removed the ivy jar that's checked in.
Merge pull request #67 from sjlee/sjlee-hadoop-2

Hadoop 2 support and ivy updates