Support options when using Stylelint with SCSS

Complement missing documentation

ale_linters/scss/stylelint.vim

@@ -1,13 +1,19 @@
 " Author: diartyz <diartyz@gmail.com>
 
 call ale#Set('scss_stylelint_executable', 'stylelint')
+call ale#Set('scss_stylelint_options', '')
 call ale#Set('scss_stylelint_use_global', get(g:, 'ale_use_global_executables', 0))
 
+function! ale_linters#scss#stylelint#GetCommand(buffer) abort
+    return '%e ' . ale#Pad(ale#Var(a:buffer, 'scss_stylelint_options'))
+    \   . ' --stdin-filename %s'
+endfunction
+
 call ale#linter#Define('scss', {
 \   'name': 'stylelint',
 \   'executable_callback': ale#node#FindExecutableFunc('scss_stylelint', [
 \       'node_modules/.bin/stylelint',
 \   ]),
-\   'command': '%e --stdin-filename %s',
+\   'command_callback': 'ale_linters#scss#stylelint#GetCommand',
 \   'callback': 'ale#handlers#css#HandleStyleLintFormat',
 \})

doc/ale-scss.txt

@@ -18,6 +18,12 @@ g:ale_scss_stylelint_executable               *g:ale_scss_stylelint_executable*
 
   See |ale-integrations-local-executables|
 
+g:ale_scss_stylelint_options                     *g:ale_scss_stylelint_options*
+                                                 *b:ale_scss_stylelint_options*
+  Type: |String|
+  Default: `''`
+
+  This variable can be set to pass additional options to stylelint.
 
 g:ale_scss_stylelint_use_global               *g:ale_scss_stylelint_use_global*
                                               *b:ale_scss_stylelint_use_global*