reverted Markdown

Markdown is a name of a language and not something that should be translated.

i18n/no.json

@@ -168,7 +168,7 @@
     "Format": "Format",
     "Plain Text": "Ren Tekst",
     "Source Code": "Kildekode",
-    "Markdown": "Oppmerket",
+    "Markdown": "Markdown",
     "Download attachment": "Last ned vedlegg",
     "Cloned: '%s'": "Kopiert: '%s'",
     "The cloned file '%s' was attached to this paste.": "Den klonede filen '%s' var koblet til denne innlimingen.",