Add support for git lfs

[jusdino]

Any chance it would be worthwhile for you guys to add support for git lfs to this layer? Or perhaps that should be something I request be added to yumda?

[mhart]

Good question – what's required to support that?

[jusdino]

I'm not sure, really. I think it would depend on how you went about installing it:
https://github.com/git-lfs/git-lfs/wiki/Installation

I tried to install with yumda using their rpm installer script, but it tries to add an external repo, which doesn't seem to work with yumda. Alternatively, it looks like they mention adding their raw binary git-lfs to anywhere in the PATH would also work, but I'm still experimenting.

I'm working on a lambda that does a git clone, zip, ship to s3 that uses this lambda layer. It works great until I try to do this with a repo that uses LFS.

[freakingawesome]

I think I've got the git-lfs installation working correctly in this forked PR. I have yet to fully vet it out by pushing up and running it as an actual Lambda Layer, but I wanted to link the in-process work here in case you wanted to take it for a spin before I fully vet it out.

I'm pretty sure it'll work just fine based on testing within the container in which it was built, but I'll report back here when I'm able to get it up on AWS for additional testing, and if it's all good I'll open a PR here.

This commit only targets the Lambda Runtime 2 (so far...).

[freakingawesome]

PR submitted. I updated it to allow specification of the git-lfs version, and I added a line in the test lambda function to run git lfs on the lambda instance, which proves that it's working correctly.