Fixing a few small things on Windows.

* No os.environ['USER'].
* get_home_dir() now first looks at %HOMESHARE% to get a UNC shared
  path if it exists.
* Minor fixes for setupbase.py.

setupbase.py

@@ -119,8 +119,8 @@ def find_packages():
     add_package(packages, 'frontend.wx')
     add_package(packages, 'gui')
     add_package(packages, 'gui.wx')
-    add_package(packages, 'kernel', config=True, tests=True, scripts=True)
-    add_package(packages, 'kernel.core', config=True, tests=True)
+    add_package(packages, 'kernel', config=False, tests=True, scripts=True)
+    add_package(packages, 'kernel.core', config=False, tests=True)
     add_package(packages, 'lib', tests=True)
     add_package(packages, 'quarantine', tests=True)
     add_package(packages, 'scripts')