Move CacheFileHeader to fileformat package.

src/main/java/cz/it4i/qcmp/cache/ICacheFile.java

 package cz.it4i.qcmp.cache;
 
+import cz.it4i.qcmp.fileformat.CacheFileHeader;
+
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;

src/main/java/cz/it4i/qcmp/cache/QuantizationCacheManager.java

@@ -2,6 +2,7 @@ package cz.it4i.qcmp.cache;
 
 import cz.it4i.qcmp.compression.CompressionOptions;
 import cz.it4i.qcmp.data.V3i;
+import cz.it4i.qcmp.fileformat.CacheFileHeader;
 import cz.it4i.qcmp.fileformat.QuantizationType;
 import cz.it4i.qcmp.quantization.scalar.SQCodebook;
 import cz.it4i.qcmp.quantization.vector.VQCodebook;

src/main/java/cz/it4i/qcmp/cache/SQCacheFile.java

 package cz.it4i.qcmp.cache;
 
+import cz.it4i.qcmp.fileformat.CacheFileHeader;
 import cz.it4i.qcmp.quantization.scalar.SQCodebook;
 
 import java.io.DataInputStream;

src/main/java/cz/it4i/qcmp/cache/VQCacheFile.java

 package cz.it4i.qcmp.cache;
 
+import cz.it4i.qcmp.fileformat.CacheFileHeader;
 import cz.it4i.qcmp.quantization.vector.VQCodebook;
 
 import java.io.DataInputStream;

src/main/java/cz/it4i/qcmp/cache/CacheFileHeader.java → src/main/java/cz/it4i/qcmp/fileformat/CacheFileHeader.java

-package cz.it4i.qcmp.cache;
+package cz.it4i.qcmp.fileformat;
 
 import cz.it4i.qcmp.data.V2i;
 import cz.it4i.qcmp.data.V3i;
-import cz.it4i.qcmp.fileformat.QuantizationType;
 import cz.it4i.qcmp.utilities.Utils;
 
 import java.io.DataInputStream;