Remove TkAgg backend if not interactive
Remove TkAgg backend if not interactive

wltrimbl/kmerspectrumanalyzer,MG-RAST/kmerspectrumanalyzer,MG-RAST/kmerspectrumanalyzer,wltrimbl/kmerspectrumanalyzer,MG-RAST/kmerspectrumanalyzer,wltrimbl/kmerspectrumanalyzer