Initial attempt at Object API

The current Object API allows to define classes and later instantiate
objects from them. This is sketchy and user code looks a bit messy, still.
But this was the primary intention for phlox, initially.

You'll find a dummy buffer class implementation in modules/test/obj.c to
test the features. It works - without memory leaks.

Also, distribute the single .gitignore into multiple ones in their
proper directories.
Object sharpening; create Object sample module

Do not expose destroy_object. Rename create_object() to new_object(). This
should be pretty much how far the engine will go about comfort. There is a
TODO left in there, though.

Create modules/samples/ directory and put an Object example inside. Really
funny.