`type -p` is not supported by /bin/sh and caused the riak and riak-admin scripts
to think that `sudo` was not available. In addition `kill -SIGNAL` is not portable
to /bin/sh and should be replaced by `kill -s SIGNAL` instead.
The portability was checked with `checkbashisms` from the devscripts package in
ubuntu 10.04 and was tested on /bin/sh in solaris, ubuntu, and OSX.