MSSQL support in ORM

**Is your feature request related to a problem? Please describe.**
Hello, I have been experimenting with `drogon` and enjoying the library!

I want to connect to a `Microsoft SQL Server` database as part of a REST API.
Is there any info for required methods that would need to be added to a potential new `MSSQLImpl` ?
I searched both issues and pull requests but did not see `MSSQL` mentioned before.

**Describe the solution you'd like**
A way to connect and interact with MSSQL databases similar to how `postgres` and `sqlite` are handled

**Describe alternatives you've considered**
I can potentially write and manage an external script/library to handle the database I/O myself outside of my drogon work.

Alternatively, a more generic ODBC ORM handler might work as well and a user can use the `ODBC Driver 17 For SQL Server` .

**Additional context**
[Some Microsoft documentation around ODBC access](https://learn.microsoft.com/en-us/sql/connect/odbc/cpp-code-example-app-connect-access-sql-db?view=sql-server-ver16)