add MIT License, possibly most liberal one.
Enhance model class with static count method which can optionally take a condition. When the clause is null/empty/falsy the where clause should not be added in the query and this may be handled in the AbstractWhereableQueryBuilder. Currently keeping it only for the count closure. later can be moved to Wherable QB.
Accept connection in constructor
Simplify creation of Gstorm instance. Add hsqldb as dependency so that caller does not need to explicitly declare the dependency. This removes lot of lines from calling groovy scripts.