fix persitant offheap issues, added tests, fixed nonshared mode.
fix persitant offheap issues, added tests, fixed nonshared mode.

RuedigerMoeller/fast-serialization,smorin/fast-serialization,janprill/fast-serialization,janprill/fast-serialization,jtsay362/fast-serialization,slburson/fast-serialization,jtsay362/fast-serialization,doubleyoung/fast-serialization,doubleyoung/fast-serialization,RuedigerMoeller/fast-serialization,slburson/fast-serialization,xamde/fast-serialization,smorin/fast-serialization,janprill/fast-serialization,RuedigerMoeller/fast-serialization,FrimaStudio/fast-serialization,xamde/fast-serialization,smorin/fast-serialization,RuedigerMoeller/fast-serialization,jtsay362/fast-serialization,doubleyoung/fast-serialization,xamde/fast-serialization,slburson/fast-serialization