fyi : changed idp.home to 'classpath:'

[Tom Zeller]

To avoid shipping test credentials, I moved them to the test
classpath, meaning from src/main/resources/creds to
src/test/resources/creds in idp-conf.

As a result, I changed the idp.home property to 'classpath:' in the
testbed, integration tests, and flow tests (in idp-conf).

See IDP-436 for more details, I am sending this note to the dev list
to point out this change.

Of course, let me know if this breaks things for you.