create_names for timers violates DRY and has scoping issues.

[PDoakORNL]

In the course of using detailed timers with TimerManager, there is repeated code used to connect time id enums and string labels. This can likely be deduplicated, also the labels and enums don't need to be in global scope and should follow the current code standards. (see WalkerLogBuffer..h:130) for fix to scoping.

Since this is a facility that is fairly new and will be added to new performance critical code it would be good if the few places it is currently used it illustrated best practice.

[prckent]

[ For those not familiar, DRY = Don't Repeat Yourself ]

Agree we should avoid repeating this code.