Revert "Declare dependencies in setup.py for automatic installation."

This reverts commit 19f850e.

This turned out to be more trouble than it's worth, since it doesn't
interact well with external installations of pycurl (e.g. from a .deb).
These dependencies are going away soon anyway.

setup.py

@@ -23,16 +23,10 @@
 except ImportError:
     pass
 
-major, minor = sys.version_info[:2]
-python_26 = (major > 2 or (major == 2 and minor >= 6))
-
-requirements = ["pycurl"]
-if not python_26:
-    # Python 2.6 includes a json module in the standard library
-    requirements.append("simplejson")
-
 # Build the epoll extension for Linux systems with Python < 2.6
 extensions = []
+major, minor = sys.version_info[:2]
+python_26 = (major > 2 or (major == 2 and minor >= 6))
 if "linux" in sys.platform.lower() and not python_26:
     extensions.append(distutils.core.Extension(
         "tornado.epoll", ["tornado/epoll.c"]))
@@ -48,7 +42,6 @@
         "tornado.test": ["README", "test.crt", "test.key"],
         },
     ext_modules = extensions,
-    install_requires = requirements,
     author="Facebook",
     author_email="[email protected]",
     url="http://www.tornadoweb.org/",