Feature Request: Add jq support

[ahochsteger]

The jq transformation language using the gojq library would be a great addition to gomplate to enable complex data processing that is often required.

Proposed Usage:

gomplate \
  -i '{{ .books | jq `[.works[]|{"title":.title,"authors":[.authors[].name],"published":.first_publish_year}]` }}' \
  -c books=https://openlibrary.org/subjects/fantasy.json

[hairyhenderson]

Hi @ahochsteger, thanks for filing this. I love jq, and occasionally find myself using it to pre-process data before feeding into gomplate, so this is a great idea!

[thesuperzapper]

@hairyhenderson I think your PR in #1585 did not actually add the JQ function, because however I try and use it, it seems to be missing:

• if I try via its alias jq I get the error function "jq" not defined"
• if I try via the coll.JQ I get the error at <coll>: can't evaluate field JQ in type interface {}"

[hairyhenderson]

@thesuperzapper what version of gomplate are you using? I don't think it made it into the 3.11.x releases...

[thesuperzapper]

@hairyhenderson ohh, I see, I was confused because I saw it on the website, I am using 3.11.5.

[hairyhenderson]

@thesuperzapper yeah - it's a pain 😢... I have #1697 to track working on fixing that 😓