ghc-HsYAML-0.2.1.0-bp153.1.20

- Update Cabal file to get more accurate dependency information.

- Update HsYAML to version 0.2.1.0.
  Upstream has edited the change log file since the last release in
  a non-trivial way, i.e. they did more than just add a new entry
  at the top. You can review the file at:
  http://hackage.haskell.org/package/HsYAML-0.2.1.0/src/ChangeLog.md

- Drop obsolete group attributes.

- Update HsYAML to version 0.1.2.0.
  * Add convenience functions `decode1` and `decode1Strict`
    expecting exactly one YAML document
    ([#5](https://github.com/haskell-hvr/HsYAML/pull/5))
  * Fix a couple corner-cases in the YAML tokenization
    ([#10](https://github.com/haskell-hvr/HsYAML/pull/10))

- Update HsYAML to version 0.1.1.3.
  * Fix bug in float regexp being too lax in the JSON and Core
    schema ([#7](https://github.com/hvr/HsYAML/issues/7))
  * Remove dependency on `dlist`

- Update Cabal build instructions to support ghc-8.6.1.

- Cosmetic: replace tabs with blanks, strip trailing white space,
  and update copyright headers with spec-cleaner.

- Add HsYAML at version 0.1.1.2.