fix: create dummy files for input/output folder

Git ignores empty folders. Both folders (input and output) are impor-
tant. Otherwise pandoc-web does not work.

Signed-off-by: Conrad Zelck <git@simpel.cc>

.gitignore

@@ -3,5 +3,7 @@ localConfig.php
 DEBUG
 _DEBUG
 input/*
+!input/dummy.txt
 output/*
+!output/dummy.txt
 

input/dummy.txt

+This file is to create the input folder. Empty folders are ignored by git.
+

output/dummy.txt

+This file is to create the output folder. Empty folders are ignored by git.
+