AWS AMI install issues...

Installing YBD on AWS own default AMI used to work, now doesn't.

Upgrading pip fails (see http://stackoverflow.com/questions/34103119/upgrade-pip-in-amazon-linux) requires that we manually do

ln /usr/local/bin/pip /usr/bin/pip

After that pip appears to behave ok, and we can run the rest of install-dependencies.sh, but ybd fails with...

[root@ip-172-31-20-238 definitions]# /src/ybd/ybd.py ci x86_64 | tee ci.master-GENIVI-M1.0.log
Traceback (most recent call last):
  File "/src/ybd/ybd.py", line 18, in <module>
    runpy.run_module('ybd')
  File "/usr/lib64/python2.7/runpy.py", line 182, in run_module
    mod_name, loader, code, fname = _get_module_details(mod_name)
  File "/usr/lib64/python2.7/runpy.py", line 111, in _get_module_details
    __import__(mod_name)  # Do not catch exceptions initializing package
  File "/src/ybd/ybd/__init__.py", line 16, in <module>
    import app
  File "/src/ybd/ybd/app.py", line 27, in <module>
    from fs.osfs import OSFS  # not used here, but we import it to check install
  File "/usr/local/lib/python2.7/site-packages/fs/osfs.py", line 21, in <module>
    from . import errors
  File "/usr/local/lib/python2.7/site-packages/fs/errors.py", line 47, in <module>
    @six.python_2_unicode_compatible
AttributeError: 'module' object has no attribute 'python_2_unicode_compatible'