update rhel6 dependency to handle glance-client install failure

This is to address the following install failure:

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INFO: @anvil.component : Setting up 1 python directories:
INFO: @anvil.component : |-- /home/openstack/glance-client/app
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ProcessExecutionError: Unexpected error while running command.
Command: python setup.py develop
Exit code: 1
Stdout: "zip_safe flag not set; analyzing archive contents...\n\nInstalled /home/openstack/glance-client/app/setuptools_git-0.4.2-py2.6.egg\nrunning develop\nrunning egg_info\ncreating python_glanceclient.egg-info\nwriting requirements to python_glanceclient.egg-info/requires.txt\nwriting python_glanceclient.egg-info/PKG-INFO\nwriting top-level names to python_glanceclient.egg-info/top_level.txt\nwriting dependency_links to python_glanceclient.egg-info/dependency_links.txt\nwriting entry points to python_glanceclient.egg-info/entry_points.txt\nwriting manifest file 'python_glanceclient.egg-info/SOURCES.txt'\nreading manifest template 'MANIFEST.in'\nwarning: no files found matching 'AUTHORS'\nwarning: no files found matching 'ChangeLog'\nwriting manifest file 'python_glanceclient.egg-info/SOURCES.txt'\nrunning build_ext\nCreating /usr/lib/python2.6/site-packages/python-glanceclient.egg-link (link to .)\nAdding python-glanceclient 0.1.1.42.1e744f1 to easy-install.pth file\nInstalling glance script to /usr/bin\n\nInstalled /home/openstack/glance-client/app\nProcessing dependencies for python-glanceclient==0.1.1.42.1e744f1\nSearching for warlock==0.1.0\nReading http://pypi.python.org/simple/warlock/\nReading http://github.com/bcwaldon/warlock\nBest match: warlock 0.1.0\nDownloading http://pypi.python.org/packages/source/w/warlock/warlock-0.1.0.tar.gz#md5=10e39eb33b44baef48686fe900c25a46\nProcessing warlock-0.1.0.tar.gz\nRunning warlock-0.1.0/setup.py -q bdist_egg --dist-dir /tmp/easy_install-5tYpCW/warlock-0.1.0/egg-dist-tmp-eC_2fH\nzip_safe flag not set; analyzing archive contents...\nAdding warlock 0.1.0 to easy-install.pth file\n\nInstalled /usr/lib/python2.6/site-packages/warlock-0.1.0-py2.6.egg\nSearching for prettytable>=0.6,<0.7\nReading http://pypi.python.org/simple/prettytable/\nReading http://code.google.com/p/prettytable/\nReading http://luke.maurits.id.au/software/prettytable/\nBest match: prettytable 0.6.1\nDownloading http://pypi.python.org/packages/source/P/PrettyTable/prettytable-0.6.1.zip#md5=2ac002f4f944f9468b0df8b4de9e8967\nProcessing prettytable-0.6.1.zip\nRunning prettytable-0.6.1/setup.py -q bdist_egg --dist-dir /tmp/easy_install-QhaUGP/prettytable-0.6.1/egg-dist-tmp-opR7Ma\n"
Stderr: 'Traceback (most recent call last):\n  File "setup.py", line 46, in <module>\n    entry_points={\'console_scripts\': [\'glance = glanceclient.shell:main\']},\n  File "/usr/lib64/python2.6/distutils/core.py", line 152, in setup\n    dist.run_commands()\n  File "/usr/lib64/python2.6/distutils/dist.py", line 975, in run_commands\n    self.run_command(cmd)\n  File "/usr/lib64/python2.6/distutils/dist.py", line 995, in run_command\n    cmd_obj.run()\n  File "/usr/lib/python2.6/site-packages/setuptools/command/develop.py", line 43, in run\n    self.install_for_development()\n  File "/usr/lib/python2.6/site-packages/setuptools/command/develop.py", line 202, in install_for_development\n    self.process_distribution(None, self.dist, not self.no_deps)\n  File "/usr/lib/python2.6/site-packages/setuptools/command/easy_install.py", line 545, in process_distribution\n    [requirement], self.local_index, self.easy_install\n  File "/usr/lib/python2.6/site-packages/pkg_resources.py", line 538, in resolve\n    dist = best[req.key] = env.best_match(req, self, installer)\n  File "/usr/lib/python2.6/site-packages/pkg_resources.py", line 780, in best_match\n    return self.obtain(req, installer) # try and download/install\n  File "/usr/lib/python2.6/site-packages/pkg_resources.py", line 792, in obtain\n    return installer(requirement)\n  File "/usr/lib/python2.6/site-packages/setuptools/command/easy_install.py", line 472, in easy_install\n    return self.install_item(spec, dist.location, tmpdir, deps)\n  File "/usr/lib/python2.6/site-packages/setuptools/command/easy_install.py", line 502, in install_item\n    dists = self.install_eggs(spec, download, tmpdir)\n  File "/usr/lib/python2.6/site-packages/setuptools/command/easy_install.py", line 681, in install_eggs\n    return self.build_and_install(setup_script, setup_base)\n  File "/usr/lib/python2.6/site-packages/setuptools/command/easy_install.py", line 958, in build_and_install\n    self.run_setup(setup_script, setup_base, args)\n  File "/usr/lib/python2.6/site-packages/setuptools/command/easy_install.py", line 947, in run_setup\n    run_setup(setup_script, args)\n  File "/usr/lib/python2.6/site-packages/setuptools/sandbox.py", line 29, in run_setup\n    lambda: execfile(\n  File "/usr/lib/python2.6/site-packages/setuptools/sandbox.py", line 70, in run\n    return func()\n  File "/usr/lib/python2.6/site-packages/setuptools/sandbox.py", line 31, in <lambda>\n    {\'__file__\':setup_script, \'__name__\':\'__main__\'}\n  File "setup.py", line 3, in <module>\n    \nImportError: cannot import name __version__\n'
AUDIT: @anvil.shell : Cmd result had exit code: 1
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