Add test from issue #54
Add test on initially initialized properties on V8Js object.
Add test on protected & private properties on derived classes
Make php_v8js_write_property export only public properties

Before a property would have been exported, even if a derived
class declared it either private or protected.
Export initially initialized public properties to V8

Before a property was exported to V8 if it was assigned a value
during normal code execution.  However if the value was assigned
(hard coded) on class level it wasn't exported.
Test export of undeclared properties in derived classes