[Translators] some typos in source

[Thomas Bellmann]

Am Sun, 21 Apr 2013 21:08:35 +0100
schrieb Paul <claws at thewildbeast.co.uk>:

> Fixed! Thanks!

You are welcome.
It seems there are two more:

#: src/mh_gtk.c:358
#, c-format
msgid ""
"Really remove the mailbox '%s' ?\n"

#: src/plugins/mailmbox/plugin_gtk.c:290
msgid ""
"Really remove the mailbox `%s' ?\n

By the way: why are sometimes the values quoted
`value' and sometimes
'value' ?

Regards
Thomas