Add web based python shell to Melange. It is accessible via http://host/admin/shell url and requires developer rights. Shell project is part of google-app-engine-samples. This commit moves django configuration from main.py to separate gae_django.py module. Shell project has been modified in order to work correctly with django 1.0+. Build script has been updated and includes shell folder and gae_django.py file. http://code.google.com/p/google-app-engine-samples/source/browse/trunk/shell/

"""
The md5 and sha modules are deprecated since Python 2.5, replaced by the
hashlib module containing both hash algorithms. Here, we provide a common
interface to the md5 and sha constructors, preferring the hashlib module when
available.
"""

try:
    import hashlib
    md5_constructor = hashlib.md5
    sha_constructor = hashlib.sha1
except ImportError:
    import md5
    md5_constructor = md5.new
    import sha
    sha_constructor = sha.new