Fix zip target deletion command in Upgrade
Add verbosity to nosetests in .travis.yml
Refactor TestDownload to isolate downloads in directory

Also concentrate on one artifact rather than downloading all of them
Add cpp artifact to the list of downloadable items

Also use the cpp artifact in the integration tests for speed optimization
Add test for unzip arguments
Fix unzipargs option in Download command

The --unzipargs '-d target' option was previously creating adding an extra
whitespace when unzipping. This commit should fix this behaviour and let the
corresponding integration test pass.
Add unzipdir optional argument to specify the target directory

- Add corresponding integration test to TestDownload class
- Pass '-q' option to unzip command in the tests
Refactor TestUpgrade and TestDownload main command into method
Revert "Fix zip target deletion command in Upgrade"

This reverts commit 48ec6567d0967b478fab27d4401273fbbdac4dd6.
Merge pull request #13 from sbesson/upgrade_fix

Allow to set target directory when unzipping artifacts