Add PrimitiveArray::reinterpret_cast

[tustvold]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

Many readers such as parquet, JSON, and IPC need the ability to promote types from their raw representation (e.g. Int64), to their semantic representation (e.g. TimestampNanosecondArray). Currently these make use of the generic cast kernels, however, these support significantly more complex forms of casting, and consequently have non-trivial dependencies,

Describe the solution you'd like

I would like a PrimitiveArray::reinterpret_cast method that can perform this operation

Describe alternatives you've considered

Additional context