* add quantity library to CEL
* add more tests to quantity
* use 1.29 env for quantity
* set CEL default env to 1.28 for 1.28 release
* add compare function
* docs and arith lib
* fixup addInt and subInt overload, add docs
* more tests
* cleanup docs
* remove old comments
* remove unnecessary cast
* add isInteger
* add overflow tests
* boilerplate
* refactor expectedResult for tests
* doc typo fix
* returns bool
* add docs link
* different dos link
* add isInteger true case
* expand iff
* add quantity back to 1.28 version, and revert change to DefaultCompatibilityVersion
* formatting
Kubernetes-commit: 423f4dfc7982136c958fc78e187c911a8896ba1b