Drop Node.js `v0.8` support
Comma-separate the `global` inline JSHint configs

According to http://www.jshint.com/docs, the variable names
after an inline `global` statement must be comma-seperated:

  "These comments start either with `jshint` or `global`
   and are followed by a comma-separated list of values"

Close h5bp/generator-h5bp#14