Remove superfluous enitity elements regarding agreements

Currently we have in the entity Agreement the fields roleTypeIdFrom and roleTypeIdTo, but we also have the entity AgreementRole regarding the identification of the parties involved and the capacity (role) in which these involved parties relate to the agreement.

Moreover, the agreementTypeId (when set - and it should be mandatory) determines the implied rolesTypes of the primary parties involved (partyIdFrom and partyIdTo), even when such roleTypes are not explicitly set as a record in <PartyRole>.

Having the functionality regarding the management of the roles of parties in relation to the agreement (entity AgreementRole) makes the two fields mentioned earlier superfluous.