Version 0.1.9 - Simplified Mixin Callable Templates.
- In class Exo_Instance_Base
-- Added static $_callable_templates[$class_name][$method_name] as a lookup table for mixin methods.
-- Added _merge_callable_templates() and called in _fixup_mixins() to populate $_callable_templates.
-- Changed _normalize_mixins() to 'private'.
-- Moved __call() to bottom of file.
- In class Exo_Implementation
-- Removed check for is_subclass_of( $owner_class, 'Exo_Mixin_Base' ) in _exo_scan_class().
- In class _Exo_Helpers
-- Changed get_class_alias() to call get_class_declaration() instead of get_class_constant().