Improved config error reporting.

rtv/exceptions.py

@@ -6,18 +6,14 @@ class EscapeInterrupt(Exception):
     "Signal that the ESC key has been pressed"
 
 
+class ConfigError(Exception):
+    "There was a problem with the configuration"
+
+
 class RTVError(Exception):
     "Base RTV error class"
 
 
-class KeystringError(RTVError):
-    "Unable to parse key string"
-
-
-class ConfigError(RTVError):
-    "There was a problem with the configuration"
-
-
 class AccountError(RTVError):
     "Could not access user account"