Log Message:
devel/py-ruamel-yaml: Update to 0.15.100

(While 0.16.1 is current, that update perhaps is more complicated, so
I'm updating to the last release of 0.15 as an intermediate step.)

[0, 15, 100]: 2019-07-17
  - fixing issue with dumping deep-copied data from commented YAML, by
    providing both the memo parameter to __deepcopy__, and by allowing
    startmarks to be compared on their content (reported by `Theofilos
    Petsios
    <https://bitbucket.org/%7Be550bc5d-403d-4fda-820b-bebbe71796d3%7D/>`__)

[0, 15, 99]: 2019-07-12
  - add `py.typed` to distribution, based on a PR submitted by
    `Michael Crusoe
    <https://bitbucket.org/%7Bc9fbde69-e746-48f5-900d-34992b7860c8%7D/>`__
  - merge PR 40 (also by Michael Crusoe) to more accurately specify
    repository in the README (also reported in a misunderstood issue
    some time ago)

[0, 15, 98]: 2019-07-09
  - regenerate ext/_ruamel_yaml.c with Cython version 0.29.12, needed
    for Python 3.8.0b2 (reported by `John Vandenberg
    <https://bitbucket.org/%7B6d4e8487-3c97-4dab-a060-088ec50c682c%7D/>`__)

[0, 15, 97]: 2019-06-06
  - regenerate ext/_ruamel_yaml.c with Cython version 0.29.10, needed for
    Python 3.8.0b1
  - regenerate ext/_ruamel_yaml.c with Cython version 0.29.9, needed for
    Python 3.8.0a4 (reported by `Anthony Sottile
    <https://bitbucket.org/%7B569cc8ea-0d9e-41cb-94a4-19ea517324df%7D/>`__)

[0, 15, 96]: 2019-05-16
  - fix failure to indent comments on round-trip anchored block style
    scalars in block sequence (reported by `William Kimball
    <https://bitbucket.org/%7Bba35ed20-4bb0-46f8-bb5d-c29871e86a22%7D/>`__)

[0, 15, 95]: 2019-05-16
  - fix failure to round-trip anchored scalars in block sequence
    (reported by `William Kimball
    <https://bitbucket.org/%7Bba35ed20-4bb0-46f8-bb5d-c29871e86a22%7D/>`__)
  - wheel files for Python 3.4 no longer provided (`Python 3.4 EOL 2019-03-18
    <https://www.python.org/dev/peps/pep-0429/>`__)