feat: Add support for using jobspec2 parser

[alexdulin]

This adds in support for using the HCL2 jobspec2 parser with a new -hcl2 flag. This allows for using new features like upstreams.datacenter and terminating gateways. It should also allow for new features in the future to be used that are only being added to the new jobspec2 parser.

Since using the jobspec2 parser and HCL2 can break existing job files, I decided to implement this as opt-in rather than opt-out, having the default be to use the original jobspec parser.

Signed-off-by: Alex Dulin [email protected]

[hashicorp-cla]

All committers have signed the CLA.

[alexdulin]

@jrasell Any chance this could get a review? Its been open for a while now and adds quite a bit of functionality and fixes to other issues people have been opening.

Apologies in advance for @'ing you directly.

[alexdulin]

@jrasell addressed all your comments in initial review. Thanks!

[alexdulin]

@tgross @jrasell I apologize for bugging you in advance, but is there any chance of this getting merged? All comments were addressed almost half a year ago and it would be great to get off of the fork of Levant we currently use, which is based on this branch.

If this MR is not going anywhere, it would be greatly appreciated to know that so we can start implementing more long term solutions on our own.

[jrasell]

@alexdulin i'll put this on my list for early this week!

[bbarman4u]

Hello team it is 2022 and seems like this important PR is still in the review stage.

[jrasell]

@alexdulin and @bbarman4u yep my bad, this slipped through the gaps. I'll try and find some time to give this another look and test.

[droustchev]

I would be really interested in seeing this PR merged in as well 👍

[mharp-zenimax]

Any chance this could get merged in?