Value filter in Path can omit closing square bracket character

A Path with a value filter is considered valid if it omits the closing `]` character, though such a Path should be considered invalid. This is something that @dvernon-uid noticed some time ago. 

Example:

``` json
{  
   "colors": [  
      "red",
      "green",
      "blue"
   ]
}
```

The path `colors[value eq \"blue\"]` is valid, as expected, but so is `colors[value eq \"blue\"`.
