Add support for more modern ES features such as class static block, class fields and private properties, nullish coalescing, BigInt and numeric separators (by switching to a better maintained fork of escodegen, @javascript-obfuscator/escodegen). #10 by @stepankuzmin

Upgrade to unassert v2 (a massive performance improvement).

• Drop support for ancient Node versions and remove transpilation of the package to ES5.
• Make sure comments are never removed by unassert. #5
• Upgrade dependencies.

• Upgrade Acorn to v6, and other dependencies to latest versions.
• Remove peerDependencies to silence any annoying warnings on install.