Breakdown getWordRec and add comments

Change-Id: I88bad8a4a8177e3540b995b664c47b86d6904027
diff --git a/native/src/defines.h b/native/src/defines.h
index aaaf348..a3edaab 100644
--- a/native/src/defines.h
+++ b/native/src/defines.h
@@ -50,4 +50,6 @@
 #define SUGGEST_MISSING_CHARACTERS true
 #define SUGGEST_MISSING_CHARACTERS_THRESHOLD 5
 
+#define MAX_WORD_LENGTH_INTERNAL 64
+
 #endif // LATINIME_DEFINES_H