Record the distro and install_type variables

We set two environment variables to record the needed info to do
conditionals in the start.sh and config-external.sh scripts

Change-Id: I08acb489e214b3dc961331bb870b435c17100635
Paritially-Implements: blueprint install-from-ubuntu

docker_templates/base/Dockerfile.j2

@@ -3,6 +3,9 @@ MAINTAINER Kolla Project (https://launchpad.net/kolla)
 
 {{ include_header }}
 
+ENV KOLLA_BASE_DISTRO {{ base_distro }}
+ENV KOLLA_INSTALL_TYPE {{ install_type }}
+
 {% if base_distro in ['fedora', 'centos', 'oraclelinux'] %}
     {% if install_type == 'binary' %}
         {% if base_distro in ['centos', 'oraclelinux'] %}