Crate persist_o_vec

The purpose of "persist-o-vec" is to:

• prevent reallocation
• remove items without shifting right to left
• re-use freed slots, pop, push, and remove, fast
• iterate over used slots only

As such, you must allocate what you need before use up to the maximum determined by the chosen indexer feature. In future there will be an option to increase the capacity if required.

Use should be similar to Vec.

WIP!

Structs

Iter
IterMut
Persist	Iteration will not always be in order