Add Obolo (ann) and Mara (mrh)

Requested at:
* https://translatewiki.net/wiki/Thread:Support/Obolo_language_localizations
* https://translatewiki.net/wiki/Thread:Support/Request_for_a_new_language.
  (The full stop is a part of the URL.)

data/langdb.yaml

@@ -21,6 +21,7 @@ languages:
   ami: [Latn, [AS], Pangcah]
   an: [Latn, [EU], aragonés]
   ang: [Latn, [EU], Ænglisc]
+  ann: [Latn, [AF], Obolo]
   anp: [Deva, [AS], अङ्गिका]
   ar: [Arab, [AF, ME], العربية]
   arc: [Syrc, [ME], ܐܪܡܝܐ]
@@ -380,6 +381,7 @@ languages:
   mo: [Cyrl, [EU], молдовеняскэ]
   moe: [Latn, [AM], innu-aimun]
   mr: [Deva, [AS, ME], मराठी]
+  mrh: [Latn, [AS], Mara]
   mrj: [Cyrl, [EU], кырык мары]
   mrv: [Latn, [PA], Magareva]
   ms: [Latn, [AS], Bahasa Melayu]