Beta 2.0

Simplify pool primitive (#63)

* LP token shares

* add wrap and unwrap, add wrapped native to constructor

* Use _wrappedNative

* Remove multicall

* WIP (test failing)

* AVAX only

* Receive AVAX and WAVAX

* Support storing in either AVAX or WAVAX

* WIP on address(0)

* Simplify pool primitive

* Remove debug code

* Make addAsset payable

* Remove unused _quoteDisable

* Make _updatePoolBalance virtual

* Remove payable

* WIP

* Support native AVAX (again)

* Fix AVAX swap

* Fix quote when paying AVAX and add tests

* WIP

* address(0) mapping

* Cleanup

---------

Co-authored-by: DocBadTouch <36558871+DocBadTouch@users.noreply.github.com>