All naked access to `ti_client` now uses the function-like-macro
to encapsulate this action. This macro existed before this just
makes all sites utilize it.
Added additional INT and PTR variants to remove the programmer
load on thinking about casing and casts polluting the point
of use. So the use now looks cleaner.
Equivalent prototypes:
void TiSetClient(Tile*, ClientData)
void TiSetClientINT(Tile*, intptr_t) /* pointertype */
void TiSetClientPTR(Tile*, void*)
ClientData TiGetClient(Tile*)
intptr_t TiGetClientINT(Tile*) /* pointertype */
void *TiGetClientPTR(Tile*)