Support for TINYINT and MEDIUMINT

[pc-jedi]

I know that TINYINT and MEDIUMINT are specific to mysql/mariadb that why I create this issue here.
Currently you can use both types but get the following warning

[WARN] Using unknown data type MEDIUMINT

Would it not be better to implement the specific types in the driver that can handle these?

I can create a PR for that, but you need to tell me how I should define the new data types, because currently they are defined in db-migrate-shared.

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[ddeath]

@pc-jedi you can bypass it with the tip mentioned here:
db-migrate/node-db-migrate#99