Adding David Mannicke's Bilby loader. re #9394

add a small dataset David provided
Modified cmake to include loadbby. re #9394

and modified loadbby to use new summary() method instead of now old SetWikiSummary and SetOptionalText methods, see http://www.mantidproject.org/Algorithm_Documentation#The_Summary_method
add rst file for bilby. re #9394
Merge branch 'feature/9394_loader_bilby_' into develop