chore: Make Travis.ci use the default 'grunt' command

The default grunt command should always pass, so Travis.ci should run that instead of a custom task list.
Merge pull request #307 from bitwiseman/fix-travis-jshint

chore: Make Travis.ci run the default 'grunt' command
chore(readme): correct links to point to testacular organization
feat(config): support running on a custom hostname

Add an optional 'hostname' parameter to the configuration
Usecases: running testacular on cloud9 and other PaaS;
legacy code that impose specific hostnames.