Index keys for hash property elements should be namespaced

[tystr]

Currently, a hashed property may have elements and if these are indexed and the key of the element is the same as a root property, the index key would collide. Prefixing the index key for hash property indexes will resolve this issue.

Take the following object:

class User
{
    /**
     * @Index
     * @Field
     **/
    protected $subscribed;

    /**
     * @Field(type="hash")
     * @Index
     **/
    protected $attributes = array();

if $attributes has an element array('subscribed' => 'yes') the resulting index key would be identical to the one used for the $subscribed property.