Removed unused imports

...c/main/scala/nl/lumc/sasc/biopet/core/BiopetQScript.scala

...main/scala/nl/lumc/sasc/biopet/core/PipelineCommand.scala

.../scala/nl/lumc/sasc/biopet/core/apps/BiopetFlagstat.scala

...c/main/scala/nl/lumc/sasc/biopet/core/config/Config.scala

...k/src/main/scala/nl/lumc/sasc/biopet/extensions/Cat.scala

...rc/main/scala/nl/lumc/sasc/biopet/extensions/Fastqc.scala

.../src/main/scala/nl/lumc/sasc/biopet/extensions/Gzip.scala

...rk/src/main/scala/nl/lumc/sasc/biopet/extensions/Ln.scala

...rc/main/scala/nl/lumc/sasc/biopet/extensions/Md5sum.scala

...c/main/scala/nl/lumc/sasc/biopet/extensions/Sha1sum.scala

...a/nl/lumc/sasc/biopet/pipelines/flexiprep/Flexiprep.scala

.../lumc/sasc/biopet/pipelines/gatk/GatkVariantcalling.scala

...n/scala/nl/lumc/sasc/biopet/extensions/aligners/Bwa.scala

.../scala/nl/lumc/sasc/biopet/extensions/aligners/Star.scala

...scala/nl/lumc/sasc/biopet/pipelines/mapping/Mapping.scala

...c/sasc/biopet/pipelines/bammetrics/PipelineTemplate.scala