Relax increment/decrement rule.

The increment/decrement rule needs to be relaxed because it's saying that `$x += 1` should be replaced with `$x++`.  The develop may intend to make the code more readable.

Citing references for this:

http://stackoverflow.com/questions/971312/why-avoid-increment-and-decrement-operators-in-javascript

While there may be valid arguments for using increment and decrement as a practice, forcing code to use them should not be part of the coding standard.