below, or relative above (uses .. to ascend the filesystem). Changed
file functions in GIB to use this. GIB can now be initialized in a
non-sandboxed mode, which at the moment means that GIB scripts run with
carne can access the entire filesystem.
to accommodate it. Added the strict flag to cbufs, which causes an error
to be generated when a command is not found instead of just warning the
user. GIB buffers have the strict flag set by default.