Add `getCurrentLocation()`/`getTokenLocation()` to replace `currentLocation()`/`currentTokenLocation()`

[cowtowncoder]

As part of on-going naming clean up for Jackson 3.x, let's change these 2 location accessor as per title.
And with some more thought, add these also as aliases in 2.13 (but not yet deprecate old variants; may do that in 2.14 or later).

[cowtowncoder]

Actually I think it'd make sense to add these aliases in 2.13 for forwards-compatibility as well, reopening.