Improve spelling correction

Handles special cases:
- word is punctuation character
- word is numerical
- word is a one-letter, uppercased word (e.g. 'I')

In these cases, returns the original word with a confidence of 1.0
Merge branch 'master' of https://github.com/clips/pattern
Implement the 'in' keyword for DOM Elements
Merge pull request #45 from sloria/in-keyword

Implement "in" keyword for DOM Elements