0.2.0-alpha.1

Features
---
- implemented chunked accessors for entity iteration
- added interface to split a storage for parallel iteration (not yet
  exposed to accessors for EntityIterator yet)

Fixes
---
- VecStorage incorrectly shrinks vector

API changes
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- decouple rctrack from global store

feat(ealloc): provide parallel entity iterators

This commit does not support parallel entity access yet.

Version 0.1.0

Initial version, a minimum viable product