Improve heat environment manager

- For underlay SSH, use "fixed" heat stack addresses
  instead of "floating". "fixed" addresses must be
  accessible from Jenkins slave node.
- do not include fuel-devops engine libraries in case if
  ENV_MANAGER is not 'devops', to avoid configuring database.
- use LAB_PARAM_DEFAULTS to specify heat template "environment"
  file with default parameters
- use required OS_USER_DOMAIN_NAME to initialize heat client.
- When heat stack is created, two parameters are passed into the
  .hot template from heat manager:

    'mcp_version': settings.MCP_VERSION
    'env_name': settings.ENV_NAME

Related-task: #PROD-27687
Change-Id: I8efcdacf6f8115e5c01c144207a2cf8a4ff9fb48
diff --git a/tcp_tests/settings_oslo.py b/tcp_tests/settings_oslo.py
index e930729..7fc8870 100644
--- a/tcp_tests/settings_oslo.py
+++ b/tcp_tests/settings_oslo.py
@@ -30,7 +30,8 @@
 _default_heat_conf = pkg_resources.resource_filename(
     __name__, 'templates/{0}/underlay.hot'.format(settings.LAB_CONFIG_NAME))
 _default_heat_env = pkg_resources.resource_filename(
-    __name__, 'templates/_heat_environments/microcloud-8116.env')
+    __name__, 'templates/_heat_environments/{0}'.format(
+        settings.LAB_PARAM_DEFAULTS))
 
 _default_salt_steps = pkg_resources.resource_filename(
     __name__, 'templates/{0}/salt.yaml'.format(settings.LAB_CONFIG_NAME))