increase timeouts for travis-ci
Merge branch 'develop' of ssh://github.com/meta-toolkit/meta into develop
Merge branch 'develop' of github.com:meta-toolkit/meta into develop
fix typo in error message
Add sample applications for printing and searching vocab maps.
Fix bug with empty string tokens being emitted by filterchains.

Allowing empty token generation caused a subtle corruption bug in the
vocabulary_map, which made the index fail to function properly.
Fix typo.
Fix bug introduced into alpha_filter by previous bugfix.
Merge branch 'develop' into classifiers