Initial commit
Rename busybox to busybox-pytia inside sandbox

This allows an environment to include another busybox if it wants to,
without interfering with the sandbox logic.
Replace init script by static C program

Keep busybox for now, but it is not needed anymore in core.
Do not let unprivileged processes shut down the vm

This patch ignores the exit status of unprivileged processes and
always continue the execution.
Handle more escape sequences in /task/control
Make files of master processes private by default
Inline cleanup

Now we are sure that we have allocated everything needed to let init
continue even if the unprivileged process has grabbed all remaining
memory.
Fix comment
Remove busybox
Reorganize
Create global out directory
Compress with LZO, disable hostfs and be quiet
Show more helpfull errors in /init
Fix cleanup in /init
Fix Go build
vm: Update UML kernel to 3.10.5

The patch to compile with glibc 2.16 is not needed anymore.
vm: Disable pid file creation in ~/.uml
vm: Suppress UML messages on start-up
vm: Get input as block device instead of stdin

Piping data into the UML (i.e., redirecting stdin) does not seem
to work. The work-around is to get the input data from /dev/ubdc.
vm: Remove start marker

Now that UML's output had been curated, we do not need the
marker anymore. The UML stdout is now exactly the output of
the task.