fix commit messages by using the stack properly (#2073)

[beckjake]

resolves #2073

Description

Actually use the stack attribute on caught exceptions, change some .node settings to use the stack.

The output of a model (x) that calls a macro (hello) with an invalid argument looks like this:

$ dbt compile
Running with dbt=0.17.0-a1
Encountered an error:
Compilation Error in model x (models/x.sql)
  macro 'dbt_macro__hello' takes no keyword argument 'invalid'

  > in macro hello (macros/hello.sql)
  > called by model x (models/x.sql)

Checklist

• I have signed the CLA
• I have run this code in development and it appears to resolve the stated issue
• This PR includes tests, or tests are not required/relevant for this PR
• I have updated the CHANGELOG.md and added information about my change to the "dbt next" section.

[drewbanin]

LGTM - nice work!