rename config.py -> configuration.py

This should help cut down on the confusion between the "config" module
and the "config" variable that everyone likes to use. The config
variable should refer to an instance of Config, whereas before it was
being shared as both the name of the module and the name of an instance.

"configuration" is always the module. "config" should always be a Config
instance.

TODO: avoid passing around a Config instance everywhere.

pokemontools/__init__.py

@@ -1,3 +1,3 @@
-import config
+import configuration as config
 import crystal
 import preprocessor

pokemontools/gbz80disasm.py

@@ -10,7 +10,7 @@ from ctypes import c_int8
 import random
 import json
 
-import config
+import configuration
 import crystal
 import labels
 import wram
@@ -929,7 +929,7 @@ class Disassembler(object):
         return (output, offset, last_hl_address, last_a_address, used_3d97)
 
 if __name__ == "__main__":
-    conf = config.Config()
+    conf = configuration.Config()
     disasm = Disassembler(conf)
     disasm.initialize()