Log Message:
Update ncdu to 1.12

1.12 - 2016-08-24
	Add NCDU_SHELL environment variable
	Add --confirm-quit flag
	Fix compilation due to missing sys/wait.h include

1.11 - 2015-04-05
	Added 'b' key to spawn shell in the current directory
	Support scanning (and refreshing) of empty directories
	Added --si flag for base 10 prefixes
	Fix toggle dirs before files