A touch of documentation.
BACKWARDS-INCOMPATIBLE-CHANGE: Making the table-name-override easier to grok, and retaining compatibility with Feincms table names by default.

The setting FEINCMSTOOLS_INCLUDE_CONTENT_TYPE_BASE_NAMES is now FEINCMSTOOLS_USE_LEGACY_TABLE_NAMES, and needs to be set to True for legacy projects that didn't already set it to False explicitly.