Teach package verifier about pipe tasks.

[porridge]

What this PR does / why we need it:

Collect keys from all pipetasks and feed that to template rendering in place of
an empty map. This has lots of room for improvement, but at least does not fail
on every single package which uses Pipe tasks.

Fixes #1398

Signed-off-by: Marcin Owsiany mowsiany@D2iQ.com

[kensipe]

@porridge as an FYI... the package verifier was intended to ignore new templating features it didn't know about... I'm on board with writing a solution for pipes... but I would like to make sure that errors are not reported for unknown features.. than fix pipe verification... perhaps this does that... I will be looking at the solution shortly.

[kensipe]

I agree with @zen-dog comments... also... It is worth the time to understand which commit caused this and why. This package verify works with kudo v0.10.x and fails with v0.11.0. There isn't a feature added that should have challenged this.

IMO there should be 2 distinct issues here:

1. what broke verification which includes pipes? how did it break and lets resolve that.
2. Adding pipes specifically as a verification feature. With this, I expect a pipe.ReferenceVerifier added to the verify.go.

With step 2 above... I would expect an error for all pipe defs which are incomplete... pipes are more difficult to know if the var is used or not... which is unfortunate... but we should ensure that the pipe task is formed well.

[porridge]

@kensipe this PR addresses the first point, I just filed #1407 about the second one.
@zen-dog I applied your suggestions.
PTAL

[zen-dog]

Lgtm 🚢

[kensipe]

woot