Initial detection for Cangjie language (#483)

Author: gtn1024

LANGUAGES.md

@@ -40,6 +40,7 @@ C++ (cc,cpp,cxx,c++,pcc,ino)
 C++ Header (hh,hpp,hxx,inl,ipp)
 Cabal (cabal)
 Cairo (cairo)
+Cangjie (cj)
 Cap'n Proto (capnp)
 Cassius (cassius)
 Ceylon (ceylon)