Add debug flag
Add debug flag

This commit contains a debug flag which can reduce the amount of
printing of tcz

GanShun/u-root,rminnich/u-root,u-root/u-root,GanShun/u-root,hugelgupf/u-root,rminnich/u-root,rminnich/u-root,hugelgupf/u-root,hugelgupf/u-root,u-root/u-root,u-root/u-root,GanShun/u-root,hugelgupf/u-root,rminnich/u-root