Co-authored-by: HHVM/Hack Open Source <hhvm-oss@fb.com>

* Configure "yes to all" per linter
fixes #86
In order to make this change backwards compatible,
allowYesToAll() defaults to true.
Unsafe linters may override this to false.
I also considered a default of false,
but that would entail altering all safe linters (including third-party).
Unsafe linters may need to suppress `must use override` linter
if they wish to remain compatible with previous versions of hhast.

* Add allowYesToAll() to unsafe linters
Some linters look like they might be unsafe, but aren't on close inspection.
I added allowYesToAll(): bool { return true; } on those.
I checked every autofixing linter.
If I could not find a bad autofix, I left the linter untouched.

* Revert allowYesToAll to true

I changed this during testing and forgot to flip it back.

* Correct mistaken variable name in comment

The example first used `$a` as a meta syntactic variable.
I later changed to `$k` and `$v` for key and value.
I didn't update every use of `$_a`.

* Move allowYesToAll() down the type hierarchy
Suggested in a code review.
This only makes sense for autofixing linters.

* Rename allowYesToAll() to areBulkAutoFixesSafe()

Co-authored-by: HHVM/Hack Open Source <hhvm-oss@fb.com>

Co-authored-by: HHVM/Hack Open Source <hhvm-oss@fb.com>

Co-authored-by: HHVM/Hack Open Source <hhvm-oss@fb.com>

Co-authored-by: HHVM/Hack Open Source <hhvm-oss@fb.com>

Co-authored-by: HHVM/Hack Open Source <hhvm-oss@fb.com>

* Document the hhast-lint.json file in detail

linters-usage.md does not document these options and suggests reading the sources instead.
Although the type is somewhat well commented,
I felt like a bit of conventional documentation would go a long way.

* Update linters-usage to refer to configuring-hhast-lint

* Make hhast a dev dependency by default

* Oops, you dropped something...

* Typo fixes

* Fix href of link and more bad spelling

* Remove lintMarkerAllowList documentation

This feature will be implemented as a linter instead.

* Document case sensitivity

Refers to: #517 (comment)

* Document the lowerCamelCase in a comment

See: #517 (comment)

* Remove section that referred to lintMarkerAllowList

This PR let `TypeRefinement` implement `ITypeSpecifier` and the update schame version to `2022-09-29-0000`, fixing the CI on `main` branch. Without this PR, many places that were `ITypeSpecifier` now become `Node`, resulting compilation errors.

Co-authored-by: HHVM/Hack Open Source <hhvm-oss@fb.com>