#4454 Clean up root test directory tests

Combine cases into smaller tests of tests and remove tests we no longer
need. Linter tests have been moved to where they should be.

test/linter/test_hadolint.vader

@@ -0,0 +1,25 @@
+Before:
+  call ale#assert#SetUpLinterTest('dockerfile', 'hadolint')
+
+After:
+  call ale#assert#TearDownLinterTest()
+
+Execute(We should not use Docker by default):
+  AssertLinter 'hadolint', 'hadolint  --no-color -'
+
+Execute(Options should be passed correctly when docker is disabled):
+  let b:ale_dockerfile_hadolint_options = '--ignore DL3006'
+
+  AssertLinter 'hadolint', 'hadolint --ignore DL3006 --no-color -'
+
+Execute(The command should be correct when using Docker):
+  let b:ale_dockerfile_hadolint_use_docker = 'always'
+
+  AssertLinter 'docker', 'docker run --rm -i hadolint/hadolint hadolint  --no-color -'
+
+Execute(The command should be correct when using docker and supplying options):
+  let b:ale_dockerfile_hadolint_use_docker = 'always'
+  let b:ale_dockerfile_hadolint_options = '--ignore DL3006'
+
+  AssertLinter 'docker',
+  \ 'docker run --rm -i hadolint/hadolint hadolint --ignore DL3006 --no-color -'