Improve guard so it works for no eof new line

ftplugin/purescript.vim

@@ -1,4 +1,5 @@
 if !exists('g:polyglot_disabled') || index(g:polyglot_disabled, 'purescript') == -1
+
 setlocal comments=s1fl:{-,mb:\ \ ,ex:-},:--\ \|,:--
 setlocal include=^import
 setlocal includeexpr=printf('%s.purs',substitute(v:fname,'\\.','/','g'))
@@ -37,4 +38,5 @@ fun! InitPureScript()
   call add(s:PS, [dir, &l:path])
 endfun
 call InitPureScript()
+
 endif