[ADD] web_tree_many2one_clickable

Clickable many2one fields for tree views
========================================

This addon provides a separate widget to allow many2one fields in a tree view
open the linked resource when clicking on their name.

You can also define a system parameter to have this behaviour for all the
existing many2one fields in tree views.

Installation
============

Install it the regular way.

Configuration
=============

If you want to have all many2one fields clickable by default, you have to
define in *Configuration > Technical > Parameters > System parameters*, a new
parameter with name `web_tree_many2one_clickable.default` and with value
`true`.

Usage
=====

For the widget option, you need to add `widget="many2one_clickable"` attribute
in the XML field definition in the tree view.

For example:

`<field name="partner_id" widget="many2one_clickable" />`

will open the linked partner in a form view.

Known issues / Roadmap
======================

* You cannot deactivate clickable behaviour for an specific many2one field if
  you configure the system parameter.
* The value of the system parameter is retrieved for each many2one field
  present in the view instead of only once.

web_tree_many2one_clickable/views/asset.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<openerp>
+    <data>
+
+        <template id="assets_backend" name="Many2one clickable assets" inherit_id="web.assets_backend">
+            <xpath expr="." position="inside">
+                <script type="text/javascript" src="/web_tree_many2one_clickable/static/src/js/web_tree_many2one_clickable.js"></script>
+            </xpath>
+        </template>
+
+    </data>
+</openerp>