MCOL-4566: Extend CompressedDBFileHeader struct with new fields.

* This patch extends CompressedDBFileHeader struct with new fields:
  `fColumWidth`, `fColDataType`, which are necessary to rebuild extent map
  from the given file. Note: new fields do not change the memory
  layout of the struct, because the size is calculated as
  max(sizeof(CompressedDBFileHeader), HDR_BUF_LEN)).

* This patch changes API of some functions, by adding new function
  argument `colDataType` when needed, to be able to call `initHdr`
  function with colDataType value.

writeengine/bulk/we_columninfo.cpp

@@ -897,7 +897,8 @@ int ColumnInfo::extendColumnOldExtent(
         }
 
         rc = colOp->expandAbbrevColumnExtent( pFile, dbRootNext,
-                                              column.emptyVal, column.width);
+                                              column.emptyVal, column.width,
+                                              column.dataType );
 
         if (rc != NO_ERROR)
         {