Few improvements

wo/cli/plugins/stack.py

@@ -1701,7 +1701,6 @@ class WOStackController(CementBaseController):
                                        ]
         except Exception as e:
             Log.debug(self, "{0}".format(e))
-            pass
 
         if (apt_packages) or (packages):
             Log.debug(self, "Calling pre_pref")

wo/core/download.py

@@ -33,12 +33,12 @@ class WODownload():
                 Log.error(self, "Unable to download file, {0}"
                           .format(filename))
                 return False
-            except urllib.error.HTTPError as e:
+            except urllib.HTTPError.error as e:
                 Log.error(self, "Package download failed. {0}"
                           .format(pkg_name))
                 Log.debug(self, "[{err}]".format(err=str(e.reason)))
                 return False
-            except urllib.error.ContentTooShortError as e:
+            except urllib.ContentTooShortError.error as e:
                 Log.debug(self, "{0}{1}".format(e.errno, e.strerror))
                 Log.error(self, "Package download failed. The amount of the"
                           " downloaded data is less than "