Use of enum DEBUG conflicts with fundamental #defines of system builds

[solas]

In NodeIDAllocator.h, Strategy enum uses DEBUG (all caps) as an enumeration, which conflicts with many arch/system builds use of that as a #define. Best to choose a different name, else, don't use ALLCAPS, which is typically always reserved for #defines only.

[yuleisui]

Can you help fix this with a pull request?