MAINT: add coveralls support for travis-ci.
ENH: actuall push for coverage reports in coverall.io.
MAINT: travis-ci test.
MAINT: travis-ci does not like not having a script entry.
MAINT: vanity commit -- add travis-ci/coverage badges.
Merge pull request #135 from enthought/test_coverage

MAINT: add coveralls support for travis-ci.