* destructuring private fields with array pattern / object pattern
* wip: new test cases
* destrucuring and rest for private properties
* test case for loose private-loose
* add transform-desturcturing for exec
* update test case
* remove getPrototypeOf imports from get and set
* wip: destructure super assignment
* throw "Destructuring to a super field is not supported yet."
* fix tests and fix assignment pattern
* remove CallExpression from AssignmentPattern
* Update member-expression-to-functions
1. Babel using British spellings, so `memoise`
2. Provide a helper `AssignmentMemoiser` class, which will assign the memo'd value with the `n`th access.
* Private properties!
* Fixes
* Tests
* Update helper name
* Fix privates that reference other privates
* Don't extend a builtin
* Rebase
