Including opaque data in scheduler request messages

If the file client_opaque.txt exists in the client data directory, it will be included in scheduler request messages as follows:

<client_opaque>
<!{CDATA[
(contents of client_opaque.txt)
]]>
</client_opaque>

and will be read into the string SCHEDULER_REQUEST::client_opaque on the server, where it can be accessed by customizable scheduler functions.

This mechanism lets you, for example, designate particular hosts as being trusted, having some software resource installed, and so on.

This is implemented in version [24586] of the server code. It will work with client versions 6.13.11+.