Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "[netconfig] APT: Prefer ipv4 connections over ipv6"
  - [netconfig] APT: Prefer ipv4 connections over ipv6

    Ubuntu prefers ipv6 connections therefore in some networks, this
    breaks software updates (it does a AAAA DNS lookup before A record
    lookups). Let's prefer old style ipv4 connections over the new ipv6 in
    order to save some processing and resource utilization.

    Based on previous work from [1] (but without /etc/gai.conf, only APT).

    [1] https://review.openstack.org/#/c/462502/

    JIRA: FUEL-321

    Change-Id: Ic3dff3baa1c0be9ac95972557d6a2d26641bfe1b
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index fedeebd..1e1ec25 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit fedeebd6ee0e3a342777812b7ea90bd4988787ad
+Subproject commit 1e1ec2526f063b6787e0980c17179ba0ee1a8174