verbosity **IS NOT** about logging level

[fxrlv]

verbosity IS NOT about logging level
grpclog package logs error by calling method (*zapGrpcLoggerV2).Error*
verbosity controls how much details we log, NOT level
could you please revert this pull request?

Originally posted by @fxrlv in #366 (comment)

[central182]

+1

The following is the default implementation of the grpclog.LoggerV2 interface and it's clear that the intention is to check
whether the verbosity of the current log (l) is within (<=) the specified threshold (g.v).
https://github.com/grpc/grpc-go/blob/41e044e1c82fcf6a5801d6cbd7ecf952505eecb1/grpclog/loggerv2.go#L199-L201

It also feels more intuitive that someone setting the threshold to level 0 (not verbose at all) doesn't want to see logs of level 2 (a bit verbose), while someone setting the threshold to level 99 (very verbose) definitely wants to see everything including logs of level 2.

The (possibly fictitious) verbosity level 99 is mentioned at https://github.com/grpc/grpc-go#how-to-turn-on-logging.

[johanbrandhorst]

Fixed in #452