Upgrade to Esprima 3.0.0-beta-3 (sebastienros#1235)

Use preview-GITHUB_RUN_NUMBER for MyGet feed version (sebastienros#1132)

Use preview-GITHUB_RUN_NUMBER for MyGet feed version (sebastienros#1132)

Upgrade Esprima to version 2.0.4 (sebastienros#1015)

Support ES2021 Logical Assignment (sebastienros#953)

Do not throw error immediately when receiving null Regex from Esprima (…

…sebastienros#931)

* enabled working regex test
* added parsing tests for [^] and [] regex patterns
* don't fail when handling null regex from esprima

Support optional catch binding (sebastienros#900)

Update appveyor.yml