pkVar is removed and slots (like wren) are implemented for accessing or passing pocketlang values to C and vice versa. Yet all the slot related functions are callable at runtime (a fiber is associated with the VM) which needs to be refactored to allocate slots even if it's not runtime, to let users make use of the pocketlang values before or without running a function.
This commit adds the builtin types to the VM's builtin classes
buffer (however no methods were added to those classes) and a super
class parameter introduced while creating a new class.
this is a part of the class implementation. In this commit classes
and instances type were completely cleaned and prepared for a new
implementation. Native class registering mechanism were fully refactored
and made it much simpler.
