Adds a basic implementation of package exceptions

Future work needs to wrap the standard exceptions in the package
exceptions and figure out what other information should be
attached to the exceptions for debug and reporting purposes.

Author: GraylinKim

sc2reader/exceptions.py

@@ -1,3 +1,16 @@
+class SC2ReaderError(Exception):
+    pass
+
+class ReadError(SC2ReaderError):
+    pass
+
+class ProcessError(SC2ReaderError):
+    pass
+
+class FileError(SC2ReaderError):
+    pass
+
+
 class ParseError(Exception):
     def __init__(self, message, replay, event, bytes):
         self.message = message
@@ -11,4 +24,4 @@ def __str__(self):
             %s""" % (self.message, self.event.type, self.event.code, self.bytes)
 
     def __repr__(self):
-        return str(self)
+        return str(self)