Added param to strain import for providing dsc_phenotypes file

* Added support for loading DSC phenotypes
* Pass path to [file](https://github.com/dictyBase/migration-data/blob/master/strain/DSC_phenotypes_import.tsv) to `--dsc_phenotypes`

**Note:**
* The [original annotated data](https://github.com/dictyBase/migration-data/blob/master/strain/DSC_phenotypes_orig.tsv) is in a slightly different format than required for [import](https://github.com/dictyBase/migration-data/blob/master/strain/DSC_phenotypes_import.tsv)