Update pytest-timeout from 1.2.0 to 1.2.1

requirements.txt

 pyparsing==2.2.0
 pytest==3.3.0
 pytest-cov==2.5.1
-pytest-timeout==1.2.0
+pytest-timeout==1.2.1
 pytest-xdist==1.20.1
 python-dateutil==2.6.1
 PyYAML==3.12