document multiple -d options
Merge branch 'master' of github.com:alexch/rerun

* 'master' of github.com:alexch/rerun:
  Configurable app name via --name
  Define missing error to prevent a NameError
document --name
Merge branch 'master' of github.com:alexch/rerun
document 'p' for pause in readme
add license to gemspec (fixes #48)