Introduce SALT_VERSION var

As we plan to move to salt 2017.7 and at the same time
we need to check 2016.3 as well (and upgrdae path), introduce
new var SALT_VERSION with default value 2016.3

Also update repo path to salt from mirror mirantis and clened up
commented hacks

Reelated: PROD-19373

Change-Id: I3c327aa4b6369750f5bdabe1b96cb52ab5770f03
diff --git a/tcp_tests/templates/physical-mcp-ocata-offline-ovs/underlay.yaml b/tcp_tests/templates/physical-mcp-ocata-offline-ovs/underlay.yaml
index db9c992..a3c7284 100644
--- a/tcp_tests/templates/physical-mcp-ocata-offline-ovs/underlay.yaml
+++ b/tcp_tests/templates/physical-mcp-ocata-offline-ovs/underlay.yaml
@@ -6,7 +6,7 @@
 
 
 {% set LAB_CONFIG_NAME = os_env('LAB_CONFIG_NAME', 'physical-mcp-ocata-offline-ovs') %}
-#{% set DOMAIN_NAME = os_env('DOMAIN_NAME', LAB_CONFIG_NAME) + '.local' %}
+{# set DOMAIN_NAME = os_env('DOMAIN_NAME', LAB_CONFIG_NAME) + '.local' #}
 {% set DOMAIN_NAME = os_env('DOMAIN_NAME', 'offline-ocata-vxlan.local') %}
 {% set HOSTNAME_APT = os_env('HOSTNAME_CFG01', 'apt.' + DOMAIN_NAME) %}
 {% set HOSTNAME_CFG01 = os_env('HOSTNAME_APT01', 'cfg01.' + DOMAIN_NAME) %}