Implement property_exists()/isset()/empty() on wrapped JavaScript objects.

Fixes issue #32.
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Merge pull request #49 from stesie/ci-badge

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Merge pull request #48 from cscott/has_prop

Implement property_exists()/isset()/empty() on wrapped JavaScript object
Make test PHP 5.3 compatible
Merge pull request #50 from stesie/fix-test-for-php53

Make test PHP 5.3 compatible
Make JavaScript function wrappers typesafe.

Use the v8::Signature parameter to FunctionTemplate::New to guarantee that
the info->Holder() is of the proper type when `php_v8js_php_callback` is
invoked.

Add test case demonstrating the segfault (which is now prevented).
Support g++-4.6 in configuration script.

gcc 4.6 doesn't have the -std=c++11 option, it uses the not-yet-finalized
-std=c++0x option.  Use whichever is found to be appropriate at configure
time.
Hookup Travis continous integration test server.
Merge pull request #51 from cscott/typesafe-func

Make JavaScript function wrappers typesafe.
Merge pull request #52 from cscott/travis

Support g++-4.6 and travis CI server.
Add v8 debug support
Unlock isolate on JS->PHP transition.
Merge pull request #53 from stesie/v8-debug

Add V8 debugging support
Call object_properties_init on newly created V8Js object.
Merge pull request #55 from stesie/call-object_properties_init

Call object_properties_init on newly created V8Js object.
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.