Add Cham languages (cja, cjm) (#384)

It's one of the languages requested at
https://phabricator.wikimedia.org/T304386
with all those scripts.

It's also configured on translatewiki, but was
never added to language-data properly.

Autonyms according to this dictionary:
Abdul Majid Hj. Yunos (2010). Kamus Cam–Melayu Jawi Rumi

data/langdb.yaml

@@ -155,7 +155,15 @@ languages:
   chr: [Cher, [AM], ᏣᎳᎩ]
   chy: [Latn, [AM], Tsetsêhestâhese]
   ciw: [Latn, [AM], Anishinaabemowin]
+  cja: [cja-latn]
+  cja-arab: [Arab, [AS], چم فور]
+  cja-cham: [Cham, [AS], ꨌꩌ ꨚꨭꩉ]
+  cja-latn: [Latn, [AS], Cam pur]
   cjk: [Latn, [AF], cokwe]
+  cjm: [cjm-cham]
+  cjm-arab: [Arab, [AS], چم فاي]
+  cjm-cham: [Cham, [AS], ꨌꩌ ꨚꨰ]
+  cjm-latn: [Latn, [AS], Cam pai]
   cjy: [Hant, [AS], 晉語]
   cjy-hans: [Hans, [AS], 晋语（简化字）]
   cjy-hant: [Hant, [AS], 晉語（正字）]
@@ -889,7 +897,7 @@ scriptgroups:
   SouthAsian: [Beng, Cakm, Deva, Gujr, Guru, Knda, Mlym, Mtei, Olck, Orya, Rohg, Saur, Sinh, Sylo, Taml, Telu, Tibt, Thaa, Wara]
   Cyrillic: [Cyrl]
   CJK: [Hani, Hans, Hant, Kore, Jpan, Yiii]
-  SouthEastAsian: [Bali, Batk, Bugi, Java, Khmr, Laoo, Lana, Mymr, Thai, Tale]
+  SouthEastAsian: [Bali, Batk, Bugi, Cham, Java, Khmr, Laoo, Lana, Mymr, Thai, Tale]
   Mongolian: [Mong]
   SignWriting: [Sgnw]
   NativeAmerican: [Cher, Cans]