Created model and migration for atr_type_selection_value table.
Readme update.
Table fix.
DataType model created.
Added third database table description.
Added doc_attribute table.
Added table  specification.
Added model DocAttributeType.
Another constant table.
Added doc_catalog table description.
Created new table .
Readme update with more spec.
Created model for doc_status.
Created table .
Created table .
Some files were left behind.
Created tables  and .
Created table 'doc_type'.
Created table 'doc_type_attribute'.
Created table 'document'.