ARROW-16772: [C++] Implement encode and decode functions for Run-Length encoding

[zagto]

[github-actions[bot]]

https://issues.apache.org/jira/browse/ARROW-16772

[github-actions[bot]]

:warning: Ticket has no components in JIRA, make sure you assign one.

[westonpace]

@drin do you want to take a look through this PR

[zagto]

@drin I hope this is not too confusing, but I did a lot of work on the rle-util branch in the recent time, which was not merged/pushed here yet, sorry for that. I'm going to push that, so that you can see the lastest version of the encode/decode kernels

Thanks for the feedback so far, I think the majority still applies to the current code. I don't think you have to review all the new rle_util code unless you want to, someone is eventually going to review ARROW-17263 for that.

[drin]

@drin ...I did a lot of work on the rle-util branch in the recent time... I'm going to push that, so that you can see the lastest version of the encode/decode kernels

Thanks for the feedback so far, I think the majority still applies to the current code. I don't think you have to review all the new rle_util code unless you want to, someone is eventually going to review ARROW-17263 for that.

just saw this comment, thanks for the heads up! I'll try to review anyways, it hopefully doesn't have too much extra learning curve