Added KRTexture::getFormat

Child class implementations are WIP

kraken/KRTexture.h

@@ -84,6 +84,7 @@ public:
   int getMinMipMap();
   bool hasMipmaps();
   virtual int getFaceCount() const = 0;
+  virtual VkFormat getFormat() const = 0;
 
   kraken_stream_level getStreamLevel(KRTexture::texture_usage_t textureUsage);
   float getLastFrameLodCoverage() const;