Add all available types for command arguments
Add all available types for command arguments

The arguments for a command can be either a string, array or map, so
these types have been added to the typings.

Signed-off-by: Cameron Diver <1d572acbfa68c7c6e541c7b840d6b622e5c0dc91@resin.io>

joyent/node-docker-file-parser