Merge pull request #120 from fzhangtj/master

fix chinese/japanese word break

Runtime/ui/txt/wordbreaker.cs

             if (this._current == this._size) {
                 return -1;
             }
-
+            
+            bool preBoundaryChar = isBoundaryChar(this._text[this._current + this._offset]);
+            if (preBoundaryChar) {
+                return this._current;
+            }
+            
+                    break;
+                }
+
+                if (isBoundaryChar(this._text[this._current + this._offset])) {
                     break;
                 }
                 var currentType = WordSeparate.classifyChar(this._text, this._current + this._offset);
             return (char) (((uint) (lead) << 10) + (uint) (trail - U16_SURROGATE_OFFSET));
         }
 
+        public static bool isBoundaryChar(char code) {
+            if (char.IsPunctuation(code)) {
+                return true;
+            }
+            if (code >= 0x4E00 && code <= 0x9FFF) { // cjk https://en.wikipedia.org/wiki/CJK_Unified_Ideographs
+                return true;
+            }
+
+            // https://social.msdn.microsoft.com/Forums/en-US/0d1888de-9745-4dd1-80fd-d3c29d3e381d/checking-for-japanese-characters-in-a-string?forum=vcmfcatl
+            if (code >= 0x3040 && code <= 0x30FF) { // Hiragana or Katakana
+                return true;
+            }
+
+            return false;
+        }
+        
         void nextUntilCodePoint() {
             while (this._current < this._size
                    && (char.IsLowSurrogate(this._text[this._current + this._offset])