check and warn for invalid partition weight

[bohhyang]

Summary

Announcer weight has been a double with no limit rules. Technically, a maximum of 100, and at most 2 digits after the decimal point should be sufficient to serve all load distribution needs in reality. With INDIS observer serving Envoy clients which require an integer uri weight, unlimited double number will cause conversion complexity that should never be encountered in real use case. In this PR, we add a max weight config which defines the max value and the number of decimal places allowed. We also added another config for the action to take when the weight rule is breached. It can be configured to ignore, log warn msg, throw exception, or rectify the value.

Note that this change will warn invalid weights set dynamically thru ZookeeperAnnouncerJmx as well.

Also added jmx methods to return the count of weight breaches for max value and decimal places, and the current markUp status of the announcer for regular cluster and dark warmup cluster respectively

See container PR for LI-specific use case and tests.

Test Done

See container PR.

[ZoabKapoor]

Overall looks good, I had one doubt about the implementation logic and also wondering if we can add a test for validatePartitionData.

Also, are we deciding not to emit a metric initially & instead rely on logs to detect use cases with invalid partition data? Or does emitting the metric not need any restli change?