Add an option to LoadInstrument to pass in the IDF XML directly.

[mantid-builder]

Original Reporter: Russell Taylor

...as an alternative to giving the filename or the instrument name.

This is needed by the SNS LiveListener, which will receive the full instrument XML description via the live stream. Although this generally ''should'' match our IDF file, it could be out of date if the installed version of Mantid is older and the stream version is the 'master' one.

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Keywords: LiveData, ADARA

[mantid-builder]

This issue was originally trac ticket 5426