Redirect parseInputs to getInputs (rebased onto develop)



This is the same as gh-2460 but rebased onto develop.

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The parseInputs method is, barring the `processFn` method completely replaceable by `client.getInputs(True)`. Made this modification and added a test.

See: https://trac.openmicroscopy.org.uk/ome/ticket/12255

A next step possibly for this PR is to make use of this method in all scripts.

/cc @will-moore @carandraug