Add ARLogv, non-variadic version of ARLog, for Swift interop.

[ibrt]

ARLog cannot be called from Swift code because variadic ObjC functions are not supported by the interop layer. I did some research and this seems to be the standard way to go about it (see for example the implementation of NSLog and NSLogv).

[DangerCI]

	:white_check_mark: Nice work.
:white_check_mark:	Please include a CHANGELOG entry. You can find it at CHANGELOG.md.

Generated by :no_entry_sign: danger

[orta]

Cool, looks good, can you add yourself to the CHANGELOG - then we're good to go 👯

[ibrt]

Done, thank you!

[orta]

Rockin!

[ibrt]

Awesome! Just a quick question, when can I approximately expect the next version to be released?

[orta]

now