[Swift-devel] wrapper and vdl-int.k updates

[Mihael Hategan]

The better error handling is in. Basically a few things were changed:

- The wrapper needs to always signal completion (whether successful or
not). Absence of such a signal is an error, most likely a shared
filesystem error.

- No more weird exit codes. Nice error messages are now sent by the
wrapper.

- Most operations done by the wrapper are error-checked. That includes
directory creation, removal, copying, whether the executable exists,
etc.

- If the application says it ran successfully, but some output files are
missing, the resulting error nicely lists all of them (missing ones).

- Info files in ${workflow directory}/info/${jobid}-info (uname, id,
env, df, /proc/cpuinfo, /proc/meminfo). These are simply collected on
the remote site for now, but it's better than nothing (since it seems
folks don't want to be bothered installing/finding kickstart).

This needs to be tested, as usual.

Mihael