Update tests_require

requirements.txt

@@ -1,3 +1,2 @@
 pycrypto>=2.6
 colorama>=0.2.4
-pexpect

setup.py

@@ -75,6 +75,7 @@ setup(name=pwman.appname,
           'Programming Language :: Python :: 2.7'
       ],
       test_suite='pwman.tests.suite',
+      tests_require=['pexpect'],
       cmdclass={
           'install_pycrypto': PyCryptoInstallCommand,
           'build_manpage': BuildManPage,