RFE: app checker use a POSIX shell for scripts

[Jeff Johnson]

+++ This bug was initially created as a clone of Bug #3308 +++

Some discussion of this point was already added in bug 3308 before it was split
off here.

2. Perhaps it would be good to test the init scripts using ash or dash to
ensure they have no BASH 'tricks' or as some may say shticks [:)] in them?
On my Debian box, dash is only 112K and only has one dynamic binary dep
[libc.so.6] so it can be easily shipped with the Linux Application Checker
package.
Since init scripts must adhere to certain criteria [such as accepting certain
arguments] I think this should be an easy enough thing to test.