[MOV] developer/misc: move all pages to a more logical location

Before this commit, the "Developer/Misc" directory of the doc, and
more particularly the "Developer/Misc/Other" sub-directory, was used as
a garbage dump where we moved all the pages that didn't fit elsewhere.
Due to that, interesting and important pages, such as the Coding
Guidelines, were buried in that directory never to be read again by Odoo
developers.

This commit moves most pages under "Misc" one or two levels up to be
located directly under "Developer" hence making them more accessible. A
new "Contributing/Development" directory is added to host the Coding
Guidelines page and soon many other pages.

task-2897143

closes odoo/documentation#2381

X-original-commit: 12ff9f118b
Signed-off-by: Antoine Vandevenne (anv) <anv@odoo.com>

content/applications/general/in_app_purchase.rst

@@ -68,4 +68,4 @@ Offering my own services
 I am more than welcome to offer my own IAP services through Odoo Apps! It is the perfect opportunity
 to get recurring revenue for an ongoing service use rather than — and possibly instead of — a sole
 initial purchase. Please, find more information at: :doc:`In-App Purchase
-</developer/misc/api/iap>`.
+</developer/api/iap>`.

content/applications/websites/website/publish/on-premise_geo-ip-installation.rst

@@ -33,7 +33,7 @@ Installation
       ./odoo-bin --geoip-db= ~/Downloads/GeoLite2-City.mmdb
 
    .. seealso::
-      - :doc:`CLI documentation </developer/misc/other/cmdline>`.
+      - :doc:`CLI documentation </developer/cli>`.
 
 .. warning::
    ``GeoIP`` Python library can also be used. However this version is discontinued since January