require SQLAlchemy >=0.9.9

[Anna Sortland]

The recent commit
https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=f1f332ad6c7fe077131cd47cbeb57a9b1efd4731
requires execution_options parameter that was added in SQLAlchemy 0.9.9. However, ceilometer still requires >=0.9.7:
https://github.com/openstack/ceilometer/blob/master/requirements.txt#L42

This causes this exception on GET /v2/events/ call:
File "/usr/lib/python2.7/site-packages/ceilometer/event/storage/impl_sqlalchemy.py", line 220, in get_events
execution_options={'isolation_level': self.isolation_level})
File "/usr/lib64/python2.7/site-packages/sqlalchemy/orm/session.py", line 851, in connection
bind = self.get_bind(mapper, clause=clause, **kw)
TypeError: get_bind() got an unexpected keyword argument 'execution_options'

Ceilometer should require SQLAlchemy >=0.9.9.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/216304

[OpenStack Infra (hudson-openstack)]

Change abandoned by Anna Sortland (<email address hidden>) on branch: master
Review: https://review.openstack.org/216304
Reason: Will update global-requirements.txt instead based on Chris' comment.

[Matthew Edmonds (edmondsw)]

global-requirements change is here: https://review.openstack.org/#/c/216360/

[Lianhao Lu (lianhao-lu)]

https://github.com/openstack/ceilometer/commit/e3ddaa3a6c280e300781383f4db1dd3c0f2bc615 fixed this