filter lanes retured by the mapping pipeline to only those requested
no need to lookup each lane since vr obj already returned
Merge pull request #174 from andrewjpage/increase_speed_of_mapping_lanes_pipeline

Increase speed of mapping lanes pipeline
vcffilter: Allow fixed threshold filtering of annotations which are not used in SOM
Merge branch 'develop' of http://github.com/VertebrateResequencing/vr-codebase into pipeline