Adjust shell scripts to allow Bash in other locations

Linux-based OS for the most part provide Bash and being located in /bin,
but on other OS's the shell would be in another location. Utilize env(1)
and allow it to be located elsewhere.

Signed-off-by: Brad Smith <brad@comstyle.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I9d4d4a3feaf993754c64b740ea91e42b336ba2b4