submit: PostgreSQL Text type compatibility fix

• Changes Text in models because starting from SQLAlchemy>=1.0 it arises an exception if the length is specified. (closes #3037)

• Adds new column 'id' with a primary key and implements upgrade recipe to modify the tables sbmFORMATEXTENSION and sbmGFILERESULT.

Signed-off-by: Leonardo Rossi <leonardo.r@cern.ch>