Added tee struct. It makes be simple by using os.MultiWriter and timeStampWriter.
Used tee struct in command. And file parameter are now received only one.
Removed dependency between ssh and coo-tee command.
Deleted unnecessary tee.Command.
Merge pull request #2 from monochromegane/remove-coo-tee-dependency

Removed dependency between ssh and coo-tee command.