Upgrade cel-python to 0.2.0

Ref: https://github.com/cloud-custodian/cel-python/releases/tag/v0.2

Relates to #180.

Author: stefanvanburen

Pipfile

@@ -4,8 +4,8 @@ verify_ssl = true
 name = "pypi"
 
 [packages]
-cel-python = "==0.1.5"
 protobuf = "==5.*"
+cel-python = "*"
 
 [dev-packages]
 pytest = "*"