Stop catching non error throwables such as SystemExit

        * Convert "except:" to "except Exception:"
        * Use log.exception instead of directly calling traceback
        * Remove unused imports
        * Fix a typos
        * Replace tabs with spaces for combatibility issues
diff --git a/TestON/tests/HATestSanity/HATestSanity.py b/TestON/tests/HATestSanity/HATestSanity.py
index 590ff56..96d0858 100644
--- a/TestON/tests/HATestSanity/HATestSanity.py
+++ b/TestON/tests/HATestSanity/HATestSanity.py
@@ -243,7 +243,7 @@
             response = main.Mininet1.getSwController( "s" + str( i ) )
             try:
                 main.log.info( str( response ) )
-            except:
+            except Exception:
                 main.log.info( repr( response ) )
             if re.search( "tcp:" + ONOS1Ip, response )\
                     and re.search( "tcp:" + ONOS2Ip, response )\
@@ -1325,7 +1325,7 @@
                 print json.dumps( json.loads( ONOS1Intents ),
                                   sort_keys=True, indent=4,
                                   separators=( ',', ': ' ) )
-            except:
+            except Exception:
                 pass
             sameIntents = main.FALSE
         utilities.assert_equals(