Hadolint is in the process of adding the severity of a lint rule to the
commandline output: https://github.com/hadolint/hadolint/pull/501
This change utilizes that to show the severity in vim.
1. The often longish `description` moved away from (supposedly short)
statusline `message` into the `detail` section.
2. dockerfile_lint sends `reference_url` pointing to issue explanations.
Use that.
* The project style linter now runs while you type.
* Now the scripts for checking the project require blank lines.
* Many style issues have been found and fixed.
* Add documentation for hadolint (doc/ale-hadolint.txt)
* Allow `hadolint` linter to run via docker image
These changes enable the `hadolint` linter to run via the author's
docker image, if present. Three modes are supported:
* never use docker;
* always use docker; and
* use docker as a failback.
* Remove 'col' from linters where it is hardcoded to 1
When 'col' is 1, the first column will get highlighted for no reason. It
should be 0 (which is the default).
In the scalac linter there was also a check about the outcome of
`stridx`. It would set l:col to 0 if it was -1, and then it uses
`'col': l:col + 1` to convert the outcome of `stridx` to the actual
column number. This will make 'col' equals 1 when there is no match. We
can remove the check because `-1 + 1 = 0`.
* Remove outdated comments about vcol
vcol was added as a default, and the loclists that follow these comments
do not contain 'vcol' anymore
