group comparison page - truncate long group names in group selector
group comparison page - truncate long group names in group selector

Signed-off-by: Abeshouse, Adam A./Sloan Kettering Institute <abeshoua@mskcc.org>

Former-commit-id: 90e8fa604030b4483be245ec41def3ab25979032
cBioPortal/cbioportal-frontend,alisman/cbioportal-frontend,cBioPortal/cbioportal-frontend,cBioPortal/cbioportal-frontend,cBioPortal/cbioportal-frontend,alisman/cbioportal-frontend,alisman/cbioportal-frontend,cBioPortal/cbioportal-frontend,alisman/cbioportal-frontend,alisman/cbioportal-frontend,cBioPortal/cbioportal-frontend,alisman/cbioportal-frontend