add example for std.stdio.stdin

Also removes some unnecessary trailing whitespace.
Nitpick: Put dots on separate lines (not at the end of the previous).

I think this is a more established formatting convention for method chaining.

Examples:
D: http://ddili.org/ders/d.en/ufcs.html (see the example at the bottom of the page).
C#: http://visualstudiomagazine.com/Articles/2013/04/10/Essential-Reactive-Extensions.aspx?Page=2
Java: http://www.oracle.com/technetwork/articles/java/ma14-java-se-8-streams-2177646.html