struct RelocationTraits

This lists a small subset of the relocation type codes for the machine.

This doesn't define each per-machine type with its own canonical name.

Instead it only the types used by modern dynamic linking ABIs. Each of

the few types actually supported for dynamic linking has the same

semantics across machines, but each machine its own different name and

type code for each one. This type uses a uniform set of names for these,

but with the actual type values each machine encodes in Elf::Rel::type().

The semantics associated with each type name are described below.

In pseudo-code expressions below, these variables are used:

* `Base` is the load bias of the relocated module (i.e. the difference

between its runtime load address and its first PT_LOAD's p_vaddr).

* `SymbolBase` is the load bias of the module defining this symbol.

* `SymbolValue` is the st_value of the defining module's symbol.

* `Addend` is r_addend or equivalent extracted (signed) value.

The datum being relocated is located at Base + r_offset.