Exit gracefully in case of error. Closes #25

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast0_0.txt

...s/Input/SmallExampleDataset_ExampleBadBlast/Blast0_0.txt~

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast0_1.txt

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast0_2.txt

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast1_0.txt

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast1_1.txt

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast1_2.txt

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast2_0.txt

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast2_1.txt

Tests/Input/SmallExampleDataset_ExampleBadBlast/Blast2_2.txt

...pleDataset_ExampleBadBlast/OrthoFinder_v0.6.1_graph.txt_0

...pleDataset_ExampleBadBlast/OrthoFinder_v0.6.1_graph.txt_1

...pleDataset_ExampleBadBlast/OrthoFinder_v0.6.1_graph.txt_2

...taset_ExampleBadBlast/OrthoFinder_v0.6.1_graph.txt_header

...Input/SmallExampleDataset_ExampleBadBlast/SequenceIDs.txt

Tests/Input/SmallExampleDataset_ExampleBadBlast/Species0.fa

Tests/Input/SmallExampleDataset_ExampleBadBlast/Species1.fa

Tests/Input/SmallExampleDataset_ExampleBadBlast/Species2.fa

.../Input/SmallExampleDataset_ExampleBadBlast/SpeciesIDs.txt

Tests/test_orthofinder.py