Make BadHashError derive from RepositoryError

This is backwards-compatible and means that most (all?) errors resulting
from suspicious or broken metadata are now RepositoryErrors.

Signed-off-by: Jussi Kukkonen <jkukkonen@vmware.com>

Author: Jussi Kukkonen

tuf/exceptions.py

@@ -66,7 +66,11 @@ class UnsupportedAlgorithmError(Error):
   """Indicate an error while trying to identify a user-specified algorithm."""
 
 
-class BadHashError(Error):
+class RepositoryError(Error):
+  """Indicate an error with a repository's state, such as a missing file."""
+
+
+class BadHashError(RepositoryError):
   """Indicate an error while checking the value of a hash object."""
 
   def __init__(self, expected_hash, observed_hash):
@@ -97,10 +101,6 @@ class UnknownKeyError(Error):
   """Indicate an error while verifying key-like objects (e.g., keyids)."""
 
 
-class RepositoryError(Error):
-  """Indicate an error with a repository's state, such as a missing file."""
-
-
 class BadVersionNumberError(RepositoryError):
   """Indicate an error for metadata that contains an invalid version number."""