Use explicit scope in all ale_linters

vint -s is now clean

ale_linters/sh/shell.vim

@@ -18,16 +18,16 @@ if !exists('g:ale_linters_sh_shell_default_shell')
 endif
 
 function! ale_linters#sh#shell#GetExecutable(buffer)
-    let banglines = getbufline(a:buffer, 1)
+    let l:banglines = getbufline(a:buffer, 1)
 
     " Take the shell executable from the hashbang, if we can.
-    if len(banglines) == 1 && banglines[0] =~# '^#!'
+    if len(l:banglines) == 1 && l:banglines[0] =~# '^#!'
         " Remove options like -e, etc.
-        let line = substitute(banglines[0], '--\?[a-zA-Z0-9]\+', '', 'g')
+        let l:line = substitute(l:banglines[0], '--\?[a-zA-Z0-9]\+', '', 'g')
 
-        for possible_shell in ['bash', 'tcsh', 'csh', 'zsh', 'sh']
-            if line =~# possible_shell . '\s*$'
-                return possible_shell
+        for l:possible_shell in ['bash', 'tcsh', 'csh', 'zsh', 'sh']
+            if l:line =~# l:possible_shell . '\s*$'
+                return l:possible_shell
             endif
         endfor
     endif
@@ -44,34 +44,34 @@ function! ale_linters#sh#shell#Handle(buffer, lines)
     "
     " bash: line 13: syntax error near unexpected token `d'
     " sh: 11: Syntax error: "(" unexpected
-    let pattern = '^[^:]\+: \%(\w\+ \|\)\(\d\+\): \(.\+\)'
-    let output = []
+    let l:pattern = '^[^:]\+: \%(\w\+ \|\)\(\d\+\): \(.\+\)'
+    let l:output = []
 
-    for line in a:lines
-        let l:match = matchlist(line, pattern)
+    for l:line in a:lines
+        let l:match = matchlist(l:line, l:pattern)
 
         if len(l:match) == 0
             continue
         endif
 
-        let line = l:match[1] + 0
-        let column = 1
-        let text = l:match[2]
-        let type = 'E'
+        let l:line = l:match[1] + 0
+        let l:column = 1
+        let l:text = l:match[2]
+        let l:type = 'E'
 
         " vcol is Needed to indicate that the column is a character.
-        call add(output, {
+        call add(l:output, {
         \   'bufnr': a:buffer,
-        \   'lnum': line,
+        \   'lnum': l:line,
         \   'vcol': 0,
-        \   'col': column,
-        \   'text': text,
-        \   'type': type,
+        \   'col': l:column,
+        \   'text': l:text,
+        \   'type': l:type,
         \   'nr': -1,
         \})
     endfor
 
-    return output
+    return l:output
 endfunction
 
 call ale#linter#Define('sh', {