add mutt for seaturtle only

mutt/mailcap

@@ -0,0 +1,18 @@
+# MS Word documents
+application/msword; ~/.mutt/view_attachment.sh %s "-" '/usr/bin/libreoffice'
+
+# Images
+image/jpg; ~/.mutt/view_attachment.sh %s jpg
+image/jpeg; ~/.mutt/view_attachment.sh %s jpg
+image/pjpeg; ~/.mutt/view_attachment.sh %s jpg
+image/png; ~/.mutt/view_attachment.sh %s png
+image/gif; ~/.mutt/view_attachment.sh %s gif
+
+# PDFs
+application/pdf; ~/.mutt/view_attachment.sh %s pdf
+
+# HTML
+text/html; ~/.mutt/view_attachment.sh %s html
+
+# Unidentified files
+application/octet-stream; ~/.mutt/view_attachment.sh %s "-"