Big changes
Add array type hint for dsn setter.
Big step forward!
Implement Delete compilation
Big step again:

    * No more Arborescence;
    * No more Options
    * QueryBuilder class in Orm
    * 60+ tests
    * Aggregates done.
fix wrong type checking
Add protection around rightHandSide conditions for compound PK
Use excluded and included keys for attributes() fn
Add options param to load()
add return to load function
Correctly update id of inserted models with composite PK
Allows insert with PK.
Add order by option.
Remove useless tests
Implement group by
Implement SelectBuilder::with()
Add protection around rightHandSide conditions for compound PK
Stuffé
Expand wildcard when select columns
Correct test