ORM for MySQL and MariaDB

[dukefirehawk]

ORM for MySQL is undergoing refactoring to get them to work with:

1. MySQL 8 and above
2. MariaDB 10.2.1 and above

ORM for Postgresql uses WITH heavily, hence it is only logical to only support MySQL versions that comes with this SQL syntax.

[dukefirehawk]

Currently, ORM for MySQL has the following pending issues:

1. mysql1 driver is unstable with MySQL 8.x.x but works fine with MariaDB 10.2.x
2. CTE is only support in MySQL 8++ and MariaDB 10.2.1. However, writable CTE is not available in both MySQL/MariaDB for insert, update and delete query. Additional query will need to be added to replicate the writable CTE functionalities.
3. No support for boolean. create table able to auto convert boolean to tinyint, but queries can only return integer type. ORM generator need to detect and recognize this through database dialect type and add in integer to boolean convertor function.
4. Both MySQL and MariaDB do not support creating foreign key for temporary tables. Removed all foreign key from SQL scripts in the unit tests.
5. MariaDB supports CAST but mysql1 driver do not recognize it as valid SQL.
6. Both MySQL/MariaDB do not support jsonb type. Removed the jsonb unit tests.

[dukefirehawk]

As ORM for MySQL and MariaDB has gone live, any additional changes or bugs will be tracked as issues.