Study view custom sample selection improvements

[kalletlak]

Currently while selecting samples/patients using custom selection, we need to enter both study ID and sample ID for multi-study queries. Instead we would want to enter only sample ID or patient ID. If they belong to multiple studies then suggest user with all possible combinations. Once a suggestion is clicked it will be added into the selection box(with <STUDY_ID>:<CASE_ID> format) and removed from suggestions.