Add filename snippets for all filetypes

.vim/snips/pandoc.snippets

@@ -638,10 +638,6 @@ snippet sketch "Link a sketch" i
 [$1](file:///home/h/sketches/$2)
 endsnippet
 
-snippet fn "Filename"
-`!p snip.rv = snip.basename`
-endsnippet
-
 snippet ` "Inline code" i
 `$1`$2
 endsnippet