Implement setup tool support for Clair

Fixes #1387

util/secscan/analyzer.py

@@ -17,10 +17,8 @@ logger = logging.getLogger(__name__)
 class LayerAnalyzer(object):
   """ Helper class to perform analysis of a layer via the security scanner. """
   def __init__(self, config, api):
-    secscan_config = config.get('SECURITY_SCANNER')
-
     self._api = api
-    self._target_version = secscan_config['ENGINE_VERSION_TARGET']
+    self._target_version = config.get('SECURITY_SCANNER_ENGINE_VERSION_TARGET', 2)
 
 
   def analyze_recursively(self, layer):
@@ -62,7 +60,6 @@ class LayerAnalyzer(object):
           - The second one is set to False when another worker pre-empted the candidate's analysis
             for us.
     """
-
     # If the parent couldn't be analyzed with the target version or higher, we can't analyze
     # this image. Mark it as failed with the current target version.
     if (layer.parent_id and not layer.parent.security_indexed and