0.8.11claws13

0.8.11claws13

* src/imap.c
        don't query imap folder for attributes because we already
        for them from imap_status

* src/mimeview.[ch]
        add support for plugable MimeViewers (unloading Viewers
        not yet complete)

* src/plugins/Makefile.am
* src/plugins/mathml_viewer/.cvsignore          ** NEW **
* src/plugins/mathml_viewer/Makefile.am         ** NEW **
* src/plugins/mathml_viewer/mathml_viewer.c     ** NEW **
        add MathML Viewer (Content-Type text/mathml) using GtkMathView
        widget from http://helm.cs.unibo.it/mml-widget/