[FIX] web: correctly init searchview when no action_id

the method prepare_dropdown_menu wasn't called when the searchview did
not have an action id.  This can cause problems in some cases (for
example, a crash in messaging when toggling the favorite menu)
[IMP] SO form clean the mess
[IMP][website_mail] improved template designer, added support for background color, font color and bootstrap buttons(inline css) in mail designer,removed other snippet, changed snippet according to new format,added theme selector in mail_designer, lodeded snippets dynamically based on theme, added font-awesome support in mail snippets, added one controller which convert font-awesome to icon

[IMP][website_mail] changed less colorpicker to inline ckeditor color picker

[IMP][website_mail] Improved discount coupon and image text snippets