src/streaming.c: Add busybox support
src/streaming.c: Add busybox support

On an embedded linux system using Busybox (https://busybox.net/),
/bin/sh (and other simple linux programs) are really just
symlinks to Busybox. Busybox then infers which program it should
run from argv[0]. This commit changes the argv[0] passed to
/bin/sh to be "sh" as opposed to "streaming" which allows Busybox
to properly infer that it needs to launch a shell.

sleepybishop/statsite,johnkeates/statsite,johnkeates/statsite,johnkeates/statsite,armon/statsite,johnkeates/statsite,librato/statsite,librato/statsite,statsite/statsite,armon/statsite,librato/statsite,armon/statsite,sleepybishop/statsite,armon/statsite,statsite/statsite,librato/statsite,statsite/statsite,statsite/statsite,sleepybishop/statsite,librato/statsite,statsite/statsite,sleepybishop/statsite,librato/statsite,armon/statsite,johnkeates/statsite,sleepybishop/statsite