reledit refactoring
* js handling rewritten to exploit all form capabilities (such as file upload ...)
* attribute-like composite relations (one ttype, cardinality in '?1' from composite side) are more
cutely handled, with a 'add'/'delete' additional actions/icons
* a reledit_ctrl rtag to finely control: reloading, edition and default values
* a proper chapter in the documentation (book)
* many bugfixes
This directory is where you should put your lax components.
For your application to actually use a component, you also
have to modify the ``INCLUDED_COMPONENTS`` variable in
the ``custom.py`` module.