ScriptContext support for nashorn

[srinivasarajuch]

Hi,

Currently, this library is providing option to set java object as a JS global variable. It is not giving an option to set ScriptContext, which is very useful feature form nashorn library to scoping the script execution as below

ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("nashorn");

// define a different script context
ScriptContext newContext = new SimpleScriptContext();
newContext.setBindings(engine.createBindings(), ScriptContext.ENGINE_SCOPE);
Bindings engineScope = newContext.getBindings(ScriptContext.ENGINE_SCOPE);

    // set the variable to a different value in another scope
    engineScope.put("x", "world");

    // evaluate the same code but in a different script context (x = "world")
    engine.eval("print(x)", newContext);

It would be very helpful if you expose the option to set the script context

[srinivasarajuch]

I have created pull request with the above changes. Please review it.

#29

[javadelight]

Thank you! The PR is included in the latest released version 0.1.5 which will be available in Maven Central shortly.