Unpin pyparsing

This was pinned in due to [1] error message
changing in pyparsing.

[1] pyparsing/pyparsing#504

setup.cfg

@@ -49,9 +49,7 @@ install_requires =
     Paste
     PasteDeploy
     daiquiri
-    # TODO(tobias-urdin): Evaluate unpin later
-    # https://github.com/pyparsing/pyparsing/issues/504
-    pyparsing>=2.2.0,<3.1.0
+    pyparsing>=2.2.0
     lz4>=0.9.0
     tooz>=1.38
     cachetools