This replaces instances of NARC IDs with type `int` or `u32` to use
`enum NarcID` instead, and replaces most instances of a NARC ID to be
named `narcID` instead of `narc`, `narcIndex` or `narcIdx`. The name
wasn't replaced where the original one was more descriptive.
* Heap_AllocFromHeapAtEnd Heap ID breadcrums
* Consistent heapID capitalization
* More Heap IDs
* A little bit more Heap IDs
* More and more Heap IDs
* Stopping for today
* MOAR
* more and more
* Back from the Heap ID mines
* A couple more
