Decompiler is strict.
Lexer tidyup.
FunctionInternals no longer uses WeakMap with bad performance.
Definitions tidyup.
Tidyup hasDirectProperty.
Strict interpreter.
Fixes #63 S15.10.7_A2_T1 Modifies lexer to discard lookahead when the value of scanOperand has changed, ensures regexp and not division is parsed for 'new /z/()'.