Make ramfs.go handle empty directories
Make ramfs.go handle empty directories

Also cleaned up ramfs.go to pass golint

Signed-off-by: Gan Shun Lim <2e7f5e6c120ad45644b6c32fd10bafcf8f554f9f@google.com>

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