Bwamem stream

Add the bwamem-stream aligner module which can potentially be a lot faster and use a lot less /tmp space than the bwamem aligner.
I meant something like the second one.

For the alignment dispatcher, it's something I'd stick in the `%VERSIONS` of `Genome::InstrumentData::Composite::Workflow` since people usually don't care.  But it would need to be exposed as a parameter that can be set on the `BwamemStream` result.

For `ReferenceAlignment`, yeah, it might end up as yet-another-processing-profile-parameter. :frowning: