Add parameter to change output stream to stderr

[bpshaver]

Users should be able to choose which output stream yaspin applies to. Halo supports a stream parameter which I'm suggesting yaspin add.

See discussion here: https://github.com/mandiant/capa/issues/1812

Tangentially related to this issue: https://github.com/pavdmyt/yaspin/issues/31

I'll give this a shot and open a PR.

[bpshaver]

https://github.com/pavdmyt/yaspin/pull/235