Fixed spelling error in example iteration.

[atomist[bot]]

Commit messages of this repository should follow the seven rules of a great Git commit message, as mentioned in the project's contributing guidelines. It looks like there's a few issues with the commit messages in this pull request:

• The first line of the commit message is the subject, and should not end with a period.
• The commit message should be written in the imperative mood, like a command, so 'Add' instead of 'Added'.