Add virtualenv submodule and simple virtualenv test

.gitmodules

@@ -7,3 +7,6 @@
 [submodule "test/integration/django"]
 	path = test/integration/django
 	url = https://github.com/django/django
+[submodule "test/integration/virtualenv"]
+	path = test/integration/virtualenv
+	url = https://github.com/dropbox/virtualenv

from_cpython/Lib/opcode.py

@@ -4,9 +4,11 @@ opcode module - potentially shared between dis and other modules which
 operate on bytecodes (e.g. peephole optimizers).
 """
 
-# Pyston change: disable this module
-raise NotImplementedError()
+# Pyston change: disable this module.
+# distutils does 'import opcode; foo(opcode.__file__)' to determine where the standard
+# library lives, so still have to provide this file as an importable module.
 
+"""
 __all__ = ["cmp_op", "hasconst", "hasname", "hasjrel", "hasjabs",
            "haslocal", "hascompare", "hasfree", "opname", "opmap",
            "HAVE_ARGUMENT", "EXTENDED_ARG"]
@@ -193,3 +195,4 @@ def_op('SET_ADD', 146)
 def_op('MAP_ADD', 147)
 
 del def_op, name_op, jrel_op, jabs_op
+"""

virtualenv @ ee62ccfd

+Subproject commit ee62ccfda4950352bcad9612f0951fb38d805350

test/integration/virtualenv_test.py

+import os
+import sys
+import subprocess
+import shutil
+
+VIRTUALENV_SCRIPT = os.path.dirname(__file__) + "/virtualenv/virtualenv.py"
+
+if os.path.exists("test_env"):
+    print "Removing the existing 'test_env/' directory"
+    subprocess.check_call(["rm", "-rf", "test_env"])
+    # shutil follows symlinks to directories, and deletes whatever those contain.
+    # shutil.rmtree("test_env")
+
+args = [sys.executable, VIRTUALENV_SCRIPT, "-p", sys.executable, "test_env"]
+print "Running", args
+subprocess.check_call(args)
+
+sh_script = """
+set -e
+python -c 'import __future__'
+python -c 'import sys; print sys.executable'
+. test_env/bin/activate
+pip install bcrypt==1.1.0
+python -c 'import bcrypt; assert bcrypt.__version__ == "1.1.0"; assert bcrypt.hashpw("password1", "$2a$12$0123456789012345678901").endswith("I1hdtg4K"); print "bcrypt seems to work"'
+""".strip()
+
+print sh_script
+subprocess.check_call(["sh", "-c", sh_script])
+