add pyparsing to build

requirements.txt

+pyparsing==2.2.0
 bcrypt==2.0.0
 certifi==2016.9.26
 cffi>=0.8.5
@@ -10,6 +11,5 @@ tornado==4.4.2
 ansible
 mercurial
 setuptools>=11.3
-#python-consul
 packaging
 appdirs
\ No newline at end of file