update default QC plex from W30467 to sequenom_fluidigm_combo
some tidy up of hardcoded paths to reference and genotype data repos
find locations of repositories with npg_tracking role
Merge pull request #52 from dozy/composite_gtck_default_qc_update

update default QC plex from W30467 to sequenom_fluidigm_combo
Changes for release 56.16
Merge pull request #53 from dozy/composite_gtck_default_qc_update

Changes for release 56.16
Merge pull request #54 from wtsi-npg/devel

Use composite data set for composite genotype check