[Fix #9957] Add WholeWord configuration to Naming/InclusiveLanguage's FlaggedTerms config

[dvandersluis]

This is a naive fix for #9957.

Allows FlaggedTerms to be set up to only match against a whole word (and enables it for slave). This allows false positives like SLAVersion and TeslaVehicle to not be flagged by the cop.

However, we don't have an inflector for identifiers, and this cop is explicitly case insensitive, which means that enabling this will also stop flagging partial word matches like DatabaseSlave. This really only affects class names since database_slave will still be flagged.

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[bbatsov]

This can also be named "PreciseMatch" or something like this. Sounds a bit more descriptive to me.

[bbatsov]

Or "ExactMatch". I think we use this somewhere else in the config. It'd be best to check, so we stay consistent with ourselves.

[dvandersluis]

We have ExactNameMatch in Style/TrivialAccessors but I don't think it exactly fits here. PreciseMatch would be ok with me but also I wanted to indicate that foo_slave would be caught, because it's a different "word". If you like PreciseMatch I'm happy to change it.

[bbatsov]

Fair point. Let's stick with WholeWord then. Naming is hard.