fix: allow debugtype 'thread' from command line
fix: allow debugtype 'thread' from command line

commit f7e9d95 [Imply single-threaded mode with -d(ebug) command line option]
was broken. It pretends to imply singlethreading each time _unless_ user
explicitly asks for the debug 'thread' option.

Change the "force singlethreading" check from

  (force single threading if last column is true)

+------------------------------------------+----------------+
|                                          |                |
+---------------------------------+        |                |
|((SINGLETHREADING   THREAD_MODE) | "AND") | "NOT"          |
+------------------+--------------+--------+----------------+
| True             |  True        |  True  |  False (wrong) |
+------------------+--------------+--------+----------------+
| True             |  False       |  False |  True          |
+------------------+--------------+--------+----------------+
| False            |  True        |  False |  True (wrong)  |
+------------------+--------------+--------+----------------+
| False            |  False       |  False |  True          |
+------------------------------------------+----------------+

To the correct one

+--------------------------------------------------+-------+
|                                                  |       |
+-----------------------------------------+        |       |
|(("NOT" SINGLETHREADING    THREAD_MODE)  | "AND") | "NOT" |
+-------------------------+---------------+--------+-------+
| False                   | True          | False  | True  |
+-------------------------+---------------+--------+-------+
| False                   | False         | False  | True  |
+-------------------------+---------------+--------+-------+
| True                    | True          | True   | False |
+-------------------------+---------------+--------+-------+
| True                    | False         | False  | True  |
+-------------------------+---------------+----------------+

Signed-off-by: Sebastian Spaeth <98dcb2717ddae152d5b359c6ea97e4fe34a29d4c@SSpaeth.de>
Signed-off-by: Nicolas Sebrecht <347709267ddd1958560c4c317ea3fd613f10a719@laposte.net>

frioux/offlineimap,frioux/offlineimap