Fix undefined class constant issue (#327)

Co-authored-by: Aleksandr Milenin <admin@azrr.info>

Fix schema specification support in WHERE clauses (#322)

* Fix bug with WHERE from other db
* Change name
* Change name back

Fix fatal error thrown if getResult() returns a boolean

$result in real can be boolean so this will fix Fatal error:  Uncaught TypeError: Return value of Envms\FluentPDO\Queries\Base::getResult() must be an instance of PDOStatement or null, bool returned

Add support for Closure types when calling debug()

Query - Add method phpdoc to support ide autocomplete

Merge pull request #275 from envms/fix/insert-execute

Add executeWithoutId() method for inserts into tables without a primary key

Merge pull request #270 from envms/update/nullValue

Update null values being skipped incorrectly

Merge pull request #267 from envms/feature/fetch-cursor

Implement fetch() cursor support

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