Updated requirements for py2.6

Author: Dan

requirements.txt

@@ -1,2 +1,3 @@
 paramiko>=1.12,!=1.16.0
-gevent>=1.1rc3
+gevent<=1.1; python_version < '3'
+gevent>=1.1; python_version >= '3'

setup.py

@@ -29,6 +29,9 @@
       packages=find_packages('.', exclude=(
           'embedded_server', 'embedded_server.*')),
       install_requires=['paramiko', 'gevent'],
+      extras_require={':python_version < "3"': ['gevent<=1.1'],
+                      ':python_version >= "3"': ['gevent>=1.1'],
+                      },
       classifiers=[
         'License :: OSI Approved :: GNU Lesser General Public License v2 (LGPLv2)',
         'Intended Audience :: Developers',