Valitron validate() fixed

/****************************/
/*        ABOUT PATCH       */
/****************************/
/*
In my application, I have a situation, where user can update some records in database.
Records which are passed as data array are updated only, so I need to validate them first.

If I use 'required' on all fields possible, then I must provide all fields on update,
so I removed 'required' parameter and only include necessary rules.

What I want to get, for example:
If I want to edit 'element_name' field, then it MUST be at least 'minLength' value 1, but with
current version, if 'element_name' is passed empty, validate() function ignores it as
says it is successfully validated which is NOT TRUE. 'element_name' is not min length 1, because it is empty!

Another case would be for 'element_quantity'. IF IT IS PASSED (not need to be), then it HAS TO BE an integer value.
Again, if I pass empty value, this is NOT an integer and if there was no 'required' field, field was ignored and
flagged as successfully validated.

*/

/****************************/
/*         EXAMPLE 1        */
/****************************/
//Input data
$data = [
    'element_name' => '' //Empty name, min lenght is NOT 1
    'element_quantity' => '' //Empty value, NOT and integer
];

//Rules
$v->rule('lengthMin', 'element_name', 1)->message(__('Name cannot be empty!'))
  ->rule('integer', 'element_quantity')->message(__('Quantity must be integer!'));

//Before PATCH
//Validation passed, 'required' options is not set, values are empty and validation ignores them! False!

//After PATCH
//Validation failed, because 'element_name' is not at least 1 character long and 'element_quantity' is NOT an integer

/****************************/
/*         EXAMPLE 2        */
/****************************/
//Input data
$data = [
    'element_name' => '' //Empty name, min lenght is NOT 1
];

//Rules in all cases
$v->rule('lengthMin', 'element_name', 1)->message(__('Name cannot be empty!'))
  ->rule('integer', 'element_quantity')->message(__('Quantity must be integer!'));

//Before
//Validation passed, 'element_name' doesn't have 'required' field set

//After
//Validation failed, 'element_name' must be at least 1 character long, IF EXISTS IN DATA ARRAY.