df: memory: opimps instantiated withconfig()

* MemoryOperationImplementationNetwork instantiates OperationImplementations
  using their `withconfig()` method, allowing them to receive arguments,
  which are taken from the uppermost level of the config, NOT addressed
  under memory-opimp-network-operation-config-key.

Fixes: #77

Signed-off-by: John Andersen <[email protected]>

Author: John Andersen

CHANGELOG.md

@@ -8,6 +8,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 - OperationImplementation add_label and add_orig_label methods now use op.name
   instead of ENTRY_POINT_ORIG_LABEL and ENTRY_POINT_NAME.
+### Fixed
+- MemoryOperationImplementationNetwork instantiates OperationImplementations
+  using their `withconfig()` method.
 
 ## [0.2.0] - 2019-05-23
 ### Added

dffml/df/memory.py

@@ -681,7 +681,7 @@ def config(cls, config, *above) -> BaseConfig:
         return MemoryOperationImplementationNetworkConfig(
                 operations={imp.op.name: imp \
                             for imp in \
-                            [Imp(BaseConfig()) \
+                            [Imp.withconfig(config, 'opimp') \
                             for Imp in cls.config_get(config, above, 'opimps')]}
             )