Use the right subprocess based on os monkeypatch

This works around the following eventlet bug:

https://bitbucket.org/which_linden/eventlet/issue/92

by using the green version of Popen if os has been
monkeypatched. It also has the side effect of making the ssl
calls not block the reactor for workers that use eventlet.

Master Change ID was: I1457237f52310f0536fbcdcaa42174b17e8edbf5

Change-Id: I5b86f9920754a6ade770a336d21072ab0f36f457
auth_token hash pki
key PKI tokens on hash in memcached when accessed by auth_token
middelware

(cherry picked from commit 75496bbe6940e72fd42dcaacbfc92b6cf92b1149)

Bug 1073343

Change-Id: I32e5481f82fd110c855d7e1138c3d43c73099bbb
Merge "Use the right subprocess based on os monkeypatch" into stable/folsom
Merge "auth_token hash pki key PKI tokens on hash in memcached when accessed by auth_token middelware" into stable/folsom