[FIX] web: force a determinist installed modules order for the assets

The backend assets includes a list of the installed modules with:
```
odoo._modules = <t t-raw="get_modules_order()"/>;
```

Because of the randomization of Python 3.5 in the dict keys,
the order of the installed modules could change from time to
time, therefore making the assets being regenerated unnecessarily

This revision is a bit linked to the below one:
f3bb9ae679

In addition to have the dict keys always in the same
order, it's important for the values to always be
the same, and it was not the case for this list
which was in the content of the backend assets,
in various order.

opw-804747

addons/web/controllers/main.py

@@ -24,6 +24,7 @@ import werkzeug
 import werkzeug.utils
 import werkzeug.wrappers
 import werkzeug.wsgi
+from collections import OrderedDict
 from werkzeug.urls import url_decode, iri_to_uri
 from xml.etree import ElementTree
 
@@ -155,10 +156,10 @@ def module_installed(environment):
     # TODO The following code should move to ir.module.module.list_installed_modules()
     Modules = environment['ir.module.module']
     domain = [('state','=','installed'), ('name','in', loadable)]
-    modules = {
-        module.name: module.dependencies_id.mapped('name')
+    modules = OrderedDict(
+        (module.name, module.dependencies_id.mapped('name'))
         for module in Modules.search(domain)
-    }
+    )
 
     sorted_modules = topological_sort(modules)
     return sorted_modules