Made data_objects dependency >= 0.9.5.
Made data_objects dependency >= 0.9.5.

DataObjects releases (like those of Extlib) are largely independent of
developments in dm-core, so we don't need to require an exact version.

engineyard/dm-core,ar-dm/ardm-core,tillsc/dm-core,joevandyk/dm-core,tpitale/dm-core,datamapper/dm-core,alloy/dm-core