Fixed typo in $where documentaion.  Issue #1317.

HTML escaping replaced with correctly-rendering characters in the $where documentation.

Before the docs read:
query.$where(function () {
  return this.comments.length &gt; 10 || this.name.length &gt; 5;
})


They now render as: 
query.$where(function () {
  return this.comments.length > 10 || this.name.length > 5;
})