v0.6.0

• Core:v = 0.16.0
• Added support for modules. This is an unofficial extension and can be disabled.
• Added ModuleResolver, FileModuleResolver and DummyModuleResolver.
• Added script execution context. It can be used to change the execution scope.
• Interpreter.exec() now executes the script in a child scope of the root scope by default.
• Interpreter.call() now uses named parameters.
• RuntimeError now includes the execution context.
• New built-in functions: Str:from_codepoint(), primitive str.codepoint_at(), require()
• Allow object property referencing with index syntax (e.g. object['key'])
• Variables defined with let are now immutable.
• NumValue's value property is now marked as final.
• Mutable variables are now disallowed in namespaces.
• Added support for nested namespaces.
• Added exists expression for checking whether a variable exists.
• Improved and rectified the behavior of Scope.
• Added Error value type.
• Json:parse now returns an Error value on failure.