[MERGE] new v8 api by rco

A squashed merge is required as the conversion of the apiculture branch from
bzr to git was not correctly done. The git history contains irrelevant blobs
and commits. This branch brings a lot of changes and fixes, too many to list
exhaustively.

- New orm api, objects are now used instead of ids
- Environements to encapsulates cr uid context while maintaining backward compatibility
- Field compute attribute is a new object oriented way to define function fields
- Shared browse record cache
- New onchange protocol
- Optional copy flag on fields
- Documentation update
- Dead code cleanup
- Lots of fixes

addons/web/static/src/xml/base.xml

@@ -465,7 +465,7 @@
 <t t-name="ViewManagerDebug">
     <option value="">Debug View#<t t-esc="view.fields_view.view_id"/></option>
     <t t-if="view_manager.active_view === 'form'">
-        <option value="perm_read">View Log (perm_read)</option>
+        <option value="get_metadata">View Metadata</option>
         <option value="toggle_layout_outline">Toggle Form Layout Outline</option>
         <option value="set_defaults">Set Defaults</option>
     </t>