The syntax for hybrid mongod command line will be:

mongod --shardsvr --hybridsvr

while not making changes in the "sharding: clusterRole: " yml params for now.

Modify the `enum class ClusterRole` to make the fields bitmask compatible so that ShardServer and ConfigServer are no longer mutually excluding. Override the '==' operator so that the compare `serverGlobalParams.clusterRole == ...` returns true on either role.

Define the `is()` method that can be used instead of `==`.

We will need to delete the operator `==` eventually when it all works at least to make sure that all occurrences are properly addressed, but we won't be able to do this for a while.