[IMP] Move 'odoorpc.service.db' module to 'odoorpc.db'
[IMP] Move 'odoorpc.service.report' module to 'odoorpc.report'
[IMP] Move 'odoorpc.service.model.model' module to 'odoorpc.models'
[IMP] Move 'odoorpc.service.model.fields' module to 'odoorpc.fields'
[IMP] Remove 'odoorpc.service' package
[IMP] Move 'odoorpc.tools.session' module to 'odoorpc.session'
[IMP] Transform 'odoorpc.tools' package to a simple module