Renaming DL3002 to Last User should not be root

and implementing it accroding to its name.

Fix rule and dockerfile

[ci skip]

Split Hadolint Dockerfile into Scratch and Debian-Slim

Used the ShellCheck AST to perform bash assertions

fixes #217

fixes #216

Implementing our own shell parser based on splititng on whitespace was
brittle, specially in the...

fixes #213

Build in Ubuntu 16.04 (xenial)

as it has no effect on issue with locale

which should solve issue with locale :crossed_fingers:

Set LC_ALL to empty before build & test

I think that Travis is setting LC_ALL in .bashrc which is overwriting
what is set in global env.

Set `LC_ALL=` for Travis

When LC_ALL is set during compilation it causes that binary is not
running in case LC_ALL is not...

Bumping parser version to 6.0.1

Use scratch as base image for distro

Update ShellCheck to 0.5.0

Upgrading the parser to version 6

fixes #203

Fix rules reporting -1 as line number

Upgraded parser version

Additionally added more strinct compiler checks and fixed them.

resolves #192

Banishing the use of head

There is no way we can make sure that using `head` is safe, so better
not use it at all. We shou...

add vscode integration

Permit squishing of single-letter options to apt-get install

add Gitlab CI example

Fixed the way pip and npm packages are found in RUN instructions

statements

fixes #181

Fixed DL3009 when using in intermediate stages

If an intermediate image is not used as the FROM clause downstream,
then there is no point in ha...

Use dropOptionsWithArg for apt-get

to be able to tolerate "target-release" option.

Switch default distro image to Debian

Added ability to ignore rules using comments in the dockerfile

[ci skip]

closes #165

Fixed FROM when specifying a registry

closes #169

Remove full stop "." from messages

Add support for "pip install ."

Simplify a logic in the check.

Linting and version check

and remove restriction for optparse-applicative.

This will save some time. We no longer need to update docker
for multistage build. Travis is now...