Merge pull request #205 from vladimir-v-diaz/develop

Address Issue #146.  Replace custom datetime format with ISO 8601.
Merge pull request #206 from vladimir-v-diaz/develop

Add Travis CI, coveralls, and coverage-related updates to modules.
Merge pull request #207 from vladimir-v-diaz/develop

Update .gitignore.
Update README.md

Add Travis CI Badge
Merge branch 'develop' of https://github.com/theupdateframework/tuf into develop