Consider native function for gzip

[AndrMoiseev]

Motivation

Grafana Operator allows provisioining of Grafana Dashboards with K8s CRD and actual dashboard json model is stored in ConfigMap. ConfigMap has a size limit 1 Mb, which can be problematic for large dashboards.
Dashboard CRD supports storing gzipped json, but as far as I know - jsonnet doesn't have any facility for gzip.

[zerok]

Hi :) Do you actually have a single dashboard that is larger than 1MB? Implementing a native function for adding gzip support is slightly problematic as that function would then only be available in the native (Go) interpreter but not in rsjsonnet et al, which some folks use in specific scenarios.