Fixes Issue 1643

Enhance K-9 Mail to be more tolerant of non-compliant IMAP servers.
Do not require a space following the + in command continuation
requests.  The rest of the token parser will swalow the space if it is
actually there but we don't really need it.

src/com/fsck/k9/mail/store/ImapResponseParser.java

@@ -182,7 +182,6 @@ public class ImapResponseParser
     private boolean parseCommandContinuationRequest() throws IOException
     {
         expect('+');
-        expect(' ');
         return true;
     }