Remove Array#commonLeft and String#trimCommonLeft

The only use case was to find common system path,
it's addressed now by `path2/common` module.
Fix isImplemented for setPrototypeOf
`implement` for `setPrototypeOf`
Fallback `Object.assign` to native
Fallback `Number.isNaN` to native
Remove obsolete index test configuration
Add introduced with ES6 `Number.EPSILON`
Add introduced with ES6 `Number.isFinite`
Add (as introduced with ES6) `Number.isInteger`
Add (as introduced with ES6) `Number.isSafeInteger`
Add (as introduced with ES6) `Number.MAX_SAFE_INTEGER`
Add (as introduced with ES6) `Number.MIN_SAFE_INTEGER`
Add (as introduced with ES6) `Math.acosh`
Add (as introduced with ES6) `Math.asinh`
Add (as introduced with ES6) `Math.atanh`
Add (as introduced in ES6) Math.cbrt
Add (as introduced in ES6) Math.cosh
Add (as introduced in ES6) Math.expm1
Add (as introduced in ES6) Math.fround
Add (as introduced in ES6) Math.hypot