[IMP] im_livechat : add nbr_sessions field on channel and modifications of various views
[IMP] im_livechat : add rule to display (or not) the support button.
[FIX] fix debug mode: correct id and xml_id (web client)

This commit fixes two issues with debug mode:
* when a default searchview is requested, it is
initialized without its view_id. Problem is that it prevents debug mode from editing the view.
*  add xml_id in Edit action form view(debug mode) : this makes the xml id visible in form view
[FIX] web: radio buttons

removed js that let user to uncheck radiobutton and from addons removed radiobuttons used for not required field except sync_typ.
changed this field as required because of functional requirement
[IMP]Export Wizard: Improve code to not remove fields from "Fields to Export"on Export all data and remove noncompatible field on selecting Import Compatible Option