Try zero padding for testing
Allow the user to specify --tight padding amount

This change does two things:

1) Provides more flexibility to the user in terms of the produced output;
2) Makes a backwards-incompatible change to the utility's interface.

This requires a major version number bump on the next release cycle.
Add HDF5 test to Travis
Bump major version to reflect interface change
Merge branch 'fix_travis_tests' into dev