Add Archlinux to list of supported distros

get_os_name returns linux-arch on Archlinux, so add a line for linux-arch to __DEF_OS_LOCATIONS.

Signed-off-by: Philippe Loctaux <loctauxphilippe@gmail.com>
Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>

offlineimap/utils/distro.py

@@ -26,6 +26,7 @@ __DEF_OS_LOCATIONS = {
     'linux-redhat': '/etc/pki/tls/certs/ca-bundle.crt',
     'linux-suse': '/etc/ssl/ca-bundle.pem',
     'linux-opensuse': '/etc/ssl/ca-bundle.pem',
+    'linux-arch': '/etc/ssl/certs/ca-certificates.crt',
 }