[DDC-3073] Add documentation about how to map column options

Adding documentation about currently accepted column options in mappings. Also providing some more examples how to map column options for each driver.
Can you add a note that these options can also be arbitrarily added and may be platform-specific?

Also, defining these options will likely break schema tool migrations, and people **WILL** open issues about them if they expect everything to run smooth (which is not the case)