Add osprofiler to global requirements

osprofiler is special designed super tiny library to make a cross
service and project profiler. It means that we will get only 1 trace
per request that goes via different services and projects.

For example if we add osprofiler to cinder and nova we can get trace
like this: http://pavlovic.me/rally/profiler/
(on graphic we are creating volume from image, then boot instance
 from volume and after all delete vm)

As library was designed specialy for OpenStack it is quite easy for
integration with it.

To make it work we need only next patches:

*) 1 patch in Ceilometer (to collect info)
   https://review.openstack.org/#/c/100239/

*) 1 patch to oslo.messaging (for cross service)
   http://goo.gl/nCK21D

*) 1 patch in all python clinet (for cross project)
   http://goo.gl/P0ocrr

*) 1 patch in all project
   http://goo.gl/yY42jd

This code should be always in source tree. Basicaly it does
nothing unit profiler is initalized.

Profiler is initialized only for request that has special
header with signed (by hmac) inforamtion. So it's safe to
keep it turned on in production.

More about lib:
https://github.com/stackforge/osprofiler/blob/master/README.rst

Change-Id: Ia4a2b2f2402ca60f25bf05c40dc07fc80c8e5ad2
Move pep8 to just 1.5.7

pep8 is just a bug fix release beyond, there are no new rules that were
not in pep8 1.5.6.

This move to 1.5.7 will help us move to flake8 2.2.0 which has no
additional rules added since flake8 2.1.0 but has parallelization turned
on by default.

Change-Id: I872a180eb066b4b85620bc03bce319345d004129
Merge "Add osprofiler to global requirements"
Merge "Move pep8 to just 1.5.7"