Add ccp show dependency tests

- Add ccp show-dep component tests
    - Add ccp show-dep error code tests
    - Add string helpers for simpler command execution result processing

Change-Id: I84d3329060f225e91c2e5ace3ebbdf441824e794

fuel_ccp_tests/helpers/utils.py

@@ -25,7 +25,6 @@ import yaml
 from fuel_ccp_tests import logger
 from fuel_ccp_tests import settings
 
-
 LOG = logger.logger
 
 
@@ -35,7 +34,6 @@ def get_test_method_name():
 
 def update_yaml(yaml_tree=None, yaml_value='', is_uniq=True,
                 yaml_file=settings.TIMESTAT_PATH_YAML):
-
     """Store/update a variable in YAML file.
 
     yaml_tree - path to the variable in YAML file, will be created if absent,
@@ -122,6 +120,25 @@ class TimeStat(object):
         return time.time() - self.begin_time
 
 
+def reduce_occurrences(items, text):
+    """ Return string without items(substrings)
+        Args:
+            items: iterable of strings
+            test: string
+        Returns:
+            string
+        Raise:
+            AssertionError if any substing not present in source text
+    """
+    for item in items:
+        LOG.debug(
+            "Verifying string {} is shown in "
+            "\"\"\"\n{}\n\"\"\"".format(item, text))
+        assert text.count(item) != 0
+        text = text.replace(item, "", 1)
+    return text
+
+
 def generate_keys():
     key = paramiko.RSAKey.generate(1024)
     public = key.get_base64()