Allow yamllint warnings to come through as ansible-lint warnings

[jwilliams-shadowsoft]

Although yamllint can be configured to generate warnings for specific rule violations, this return does not seem to be passed back up to ansible-lint.

For instance, assuming I don't want to have multiple spaces after a colon be an error, I could (in the yamllint config):

rules:
  colons:
    level: warning

But there does not seem to be a way to represent this in the ansible-lint config file. You can only make all yaml rule violations warnings or skips.

Other options added to the yamllint file seem to work fine, like "disable" or setting the "truthy" values:

rules:
  colons: disable
  truthy:
    allowed-values:
    - "yes"
    - "no"
    - "true"
    - "false"

Just opting for the most configurability we can get here.