Engine 0.20.6

- added support for recalculation of Apple-specific free space offset
value stored in volume's ZeroVector. Thanks to osxreverser for reporting
the issue #29.
- ZeroVectorCRC renamed to AppleCRC32, because it's Apple-specific after
all.
- ParsingData handling removed from old codebase, because it's only
needed for the new engine.

uefitool.cpp

@@ -17,7 +17,7 @@
 UEFITool::UEFITool(QWidget *parent) :
 QMainWindow(parent),
 ui(new Ui::UEFITool), 
-version(tr("0.20.5"))
+version(tr("0.20.6"))
 {
     clipboard = QApplication::clipboard();