Add --no-default-permissions flag based on latest fuse library.

[Arcayr]

As per #590.

This also includes an updated fuse library which had some mandatory changes to elsewhere in the codebase.

[kahing]

any reason to use this instead of say, --dir-mode=0777 --file-mode=0666?

[Arcayr]

S3 doesn't really have a unix-like permissions model, as far as I'm aware. But mostly for consistency with similar implementations, if I may copy the commentary from the fuse library prior to my changes:

// Note that in contrast to the defaults for FUSE, this package mounts file
// systems in a manner such that the kernel checks inode permissions in the
// standard posix way. This is implemented by setting the default_permissions
// mount option (cf. http://goo.gl/1LxOop and http://goo.gl/1pTjuk).