analytic_fields_view_get: fixed an issue when using the oe_analytic div for tree views. Fields are now generated with an empty JSON dict as their default 'modifiers' attribute.

Bound dimensions: if an analytic code ID is passed to create or write, it will be ignored unless the key "force_code_id" is set to True in the context.

Add some help

- "Structure" -> "Structures"

extract_values can be used to copy analytic (or para-analytic) data from an object to another.
format_field_name returns an analytic field's name from its slot, prefix and suffix.

Fixed a bug that could break views when using the oe_analytic div without any analytic field to place.

Para-analytic are created and named according to the structure but do not take analytic codes as values. Instead, they can be any kind of field.

The analytic_structure method analytic_fields_subview_get allow any model (not necessarily one that implements MetaAnalytic) to display the analytic fields of models that have subviews defined inside its views. It is still strongly recommended to use ir.ui.view records and the [type]_view_ref context key instead.