Minor fixes to build process.

* Fix name error when running setup.py from within main package.

* Change `make clean` so that it removes hash files.

* Remove unused import.

Makefile

@@ -5,7 +5,7 @@ all:
 	git update-index --assume-unchanged skimage/version.py
 
 clean:
-	find . -name "*.so" -o -name "*.pyc" | xargs rm -f
+	find . -name "*.so" -o -name "*.pyc" -o -name "*.pyx.md5" | xargs rm -f
 
 test:
 	nosetests skimage

skimage/setup.py

@@ -22,7 +22,7 @@ def configuration(parent_package='', top_path=None):
             config.add_data_dir(dirname)
 
     # Add test directories
-    from os.path import isdir, dirname, join, abspath
+    from os.path import isdir, dirname, join
     rel_isdir = lambda d: isdir(join(curpath, d))
 
     curpath = join(dirname(__file__), './')
@@ -35,6 +35,6 @@ def configuration(parent_package='', top_path=None):
 if __name__ == "__main__":
     from numpy.distutils.core import setup
 
-    config = Configuration(top_path='').todict()
+    config = configuration(top_path='').todict()
     setup(**config)