DamageProfier exits 0 even if no output files

[jfy133]

Workaround: make all DamageProfiler output (txt/pdf/json) optional True. Log is still created but just reports all reads as 0.

Will also report upstream.

[apeltzer]

Yeah clearly an upstream bug that needs to be fixed/adjusted maybe. Although reporting zeros everywhere shouldn't be a bug actually ... (?)

[jfy133]

No, it's not. But I'm wondering why it can't also produce all the output files with 0s anyway.

Maybe I'm being too MultiQC centric now (thinking a user might be confused why there aren't damage curves for their given sample...)