Add best practice to add version to data table for new data managers

[paulzierep]

In light of GTA and the general issue. For tools where only specific tools work with specific versions of a DB it's a pain to maintain tool-DB relations if no version is added to data tables and if tools are not restricting the version they can use.
To at least reduce the work in the future, I would propose to make it mandatory for new IUC data managers to add a version column to the data table and add a filter to the tool like:

  <options from_data_table="gtdbtk_database_versioned">
      <filter type="regexp" column="version" value="^2(07|14)$"/>

I can add the information as a PR, but was not sure where in the docs this should go ?