postCommitBuildTrigger.sh for svn asks for sh, but actually needs bash

As currently supplied, the postCommitBuildTrigger.sh script yields the following error on some platforms (e.g. Ubuntu):

postCommitBuildTrigger.sh: 22: 1: not found

This can be rectified by editing the first line to read:

#! /bin/bash

We should also check other triggering scripts.