Delly Importer Changes

[willrockout]

I added the option to incorporate delly vcf files. Had a couple question to go along with my changes noticed when i changed metasv locally the changes wouldn't go into effect unless i moved run_metasv.py out of the scripts directory back into the general metasv directory wanted to see if you knew a possible reason for that? Second wasn't sure what to default CTX variant lengths too and was wondering if you had a preference? Seems like other callers pick random numbers but since metasv has a min sv length setting wanted to check.