adding some disclaimer

ktx2Decoder/README-ES6.md

@@ -1 +1,2 @@
-KTX2 Decoder
+KTX2 Decoder
+!!! Experimental Extension Subject to Changes !!!

ktx2Decoder/README.md

@@ -1,3 +1,5 @@
 # Babylon.js KTX2 Decoder
 
 An extension to decode ktx2 files.
+
+!!! Experimental Extension Subject to Changes !!!

ktx2Decoder/src/ktx2Decoder.ts

@@ -57,6 +57,7 @@ const isPowerOfTwo = (value: number)  => {
 
 /**
  * Class for decoding KTX2 files
+ * 
  */
 export class KTX2Decoder {