Work around flash writes not starting from the first cluster.

Fixes #8.
Merge branch 'next' into direntrydebug
Define boot sector in a struct for easy of debugging.
Merge branch 'next' into direntrydebug
Define boot sector in a struct for easy of debugging.
Merge branch 'next' into direntrydebug

Conflicts:
	src/disk.h
	src/diskimage.c
Use uint* types instead of unsigned char/short/int.
Merge branch 'next' into direntrydebug