Rust wc

So in my attempt to practice writing POSIX command-line tools in Rust, the next tool I tried to rewrite was wc (or word count). This is a simple tool that counts 4 things:

• lines (separated by U+0D, LINE FEED)
• words (separated by any whitespace)
• characters (multibyte encoded, probably UTF-8)
• bytes

In the interest of brevity, I'm going to refer the reader to this link for the source code. One thing I learned is that the current std::getopts library doesn't have many features, e.g., it doesn't link short options and long options, so you have to check each separately. While I was writing this, some people in #rust on irc.mozilla.org suggested that I look at docopt which has not been ported to Rust yet, still mostly a Python library, but if ported would make a great addition to the language.