Implement with no GeneralizedFile.

* src/dctc/java/com/dataiku/dctc/AutoGZip.java: Retrieve the old
  implementation.
Extends AutoGZip for bz2.

* src/dctc/java/com/dataiku/dctc/AutoGZip.java: Here.
tar: Manage tar{,.bz2,.gz} tarball.

Closes #69.

* src/dctc/java/com/dataiku/dctc/GlobalConstants.java: Add the extension as constants.
* src/dctc/java/com/dataiku/dctc/archive/TarInputArchiveEntry.java,
  src/dctc/java/com/dataiku/dctc/archive/TarInputArchiveIterable.java,
  src/dctc/java/com/dataiku/dctc/archive/TarInputArchiveIterator.java: Tar iterator
* src/dctc/java/com/dataiku/dctc/copy/SimpleCopyTaskRunnableFactory.java,
  src/dctc/java/com/dataiku/dctc/archive/ArchiveFactory.java:
  tar{,.bz2,.gz} management.