#1 Produces no output with no template file

[Nigel Swinson]

If you do not specify a IndexTemplateFile but do
specify a ScriptRoot, then it opens the ScriptRoot
directory and tries to interpret it as a template
file. It succeeds but reads no data and as a result
you end up with a null template file, and hence no <!--
ExplorerIndex#Index--!> so no index is generated.

The fix is to only use the ScriptRoot if the
IndexTemplateFile exists.

Nigel