Use POSIX shell in scripts

[czarkoff]

Some systems don't have bash at /bin/bash, or may use other shells by default

[tdaede]

Did you verify that the scripts work on other sh implementations?

Indeed, other systems might use other default shells, which is why bash is explicitly specified.

I'm not sure this patch will fix more than it breaks - we don't currently have a way to prevent bash-isms from slipping into scripts.

[czarkoff]

I verified some with ksh.