(WIP) Use dynamic IPv4 network pools for deploy clusters (#18)

*     Use dynamic IPv4 network pools for deploy clusters

    - Use 'config' object as an additional jinja option to load templates
    - Use 'address_pools' from 'config' object in
      virtual-mcp11-ovs and virtual-mcp11-dvr
    - Fill 'address_pools' in 'config' object from fuel-devops manager

*     Use dynamic IPv4 network pools for deploy clusters

    - Use 'config' object as an additional jinja option to load templates
    - Use 'address_pools' from 'config' object in
      virtual-mcp11-ovs and virtual-mcp11-dvr
    - Fill 'address_pools' in 'config' object from fuel-devops manager

* return removed 'test_install_k8s'

* Use 'sed' to replace IP addresses in the models to pre-generated

also, two new environment variables avaliable for mcp11-ovs/dvr:
- SALT_MODELS_REPOSITORY
- SALT_MODELS_COMMIT

* remove temporary env_config.py.bak
diff --git a/tcp_tests/helpers/utils.py b/tcp_tests/helpers/utils.py
index 28314f6..9501e01 100644
--- a/tcp_tests/helpers/utils.py
+++ b/tcp_tests/helpers/utils.py
@@ -318,7 +318,7 @@
         self.write_content()
 
 
-def render_template(file_path):
+def render_template(file_path, options=None):
     required_env_vars = set()
     optional_env_vars = dict()
     def os_env(var_name, default=None):
@@ -334,9 +334,10 @@
 
         return var
 
-    options = {
-        'os_env': os_env,
-    }
+    if options is None:
+        options = {}
+    options.update({'os_env': os_env,})
+
     LOG.info("Reading template {0}".format(file_path))
 
     path, filename = os.path.split(file_path)
@@ -355,12 +356,6 @@
     return template
 
 
-def read_template(file_path):
-    """Read yaml as a jinja template"""
-    template = render_template(file_path)
-    return yaml.load(template)
-
-
 def extract_name_from_mark(mark):
     """Simple function to extract name from pytest mark