* Remove positional capture mode
* Compute hash value for each AST node
* Better code for hash value building
* Fix : no hash value computed for {find, _} expressions.

These expressions are used internally only, to build list matching functions.
* Compute smaller hash values
* Add ejpet_generator module

This module manages caching of already seen matching functions. Backend modules recur through that module.
* Change hash value of {inject, Type, Name} form. Key is more readable.
* Update parser tests.
* Add cache support, with a default implementation.