mod_invites_page: Change client selection button text from 'Install' to 'Select' by default This also allows specific clients entries to override the text via the 'select_text' field. Rationale: 1) users may already have the software installed, we still want them to select it anyway for the tailored setup experience. 2) some clients (e.g. web clients) are not really "installed" so the text was misleading

Introduction
============

This module attempts to sanitize XHTML-IM messages.

It does **not** attempt to sanitize any CSS embedded in `style`
attributes, these are instead stripped by default.

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

  Option                   Type      Default
  ------------------------ --------- ---------
  `strip_xhtml_style`      boolean   `true`
  `bounce_invalid_xhtml`   boolean   `false`