message: added length and is docs closes
diff: @@ -251,6 +251,32 @@ The field under validation must be equal to the first argument passed, uses `===
  <input v-model="confirmation" type="text" name="password_confirmation">
  ```
  +## is_not
  +
  +A negated version of [is](#is) rule, also uses the `===` for equality checks.
  +
  +### is_not params
  +
  +- `value:` A value of anytype to be compared against the field value.
  +
  +```html
  +<input v-validate="{ is_not: duplicate }" type="text" name="field">
  +<input v-model="duplicate" type="text" name="not_again">
  +```
  +
  +## length
  +
  +The field under validation must be an iterable and/or have a length property of the specified amount. If another value is provided it forces the length check to be between those values in a min/max fashion.
  +
  +### length params
  +
  +- `len:` The length the iterable should exactly have. If max is provided it will act as a `min` length check.
  +- `max:` The maximum length the iterable should have. Optional.
  +
  +```html
  +<input v-validate="'length:5'" type="text" name="field">
  +```
  +
  ## max
  The field under validation length may not exceed the specified length.
  