[ajax] improve backward compatibility for redefined ajax functions (closes #2447189)
If an ajax function from stdlib (e.g. js_reledit_form) was redefined in a cube,
the cube version should still takes the precedence<
=> check for existing ajax function on deprecated controller _before_ checking
ajax function availability on the new one.
Schema of the data
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First take a look at the data schema_ then try to remember that you are browsing
through a heap of data by applying stylesheets to the results of queries. This
site is not a content management system with items placed in folders. It is an
interface to a database which applies a view to retreived data.
.. _schema: schema