sample filter: default hard cutoffs

[allonw]

The current default cutoffs are: hard_ralign = 15; hard_breadth = 0.2.

From what I see, this is suitable to genome alignment but way too harsh for transcriptome alignment. My cutoffs for transcriptome are: hard_ralign = 5; hard_breadth = 0.1.

In the meantime I added "..." to easybake's arguments that allows the user to pass params to the filter and scone (instead of adding zillion params to the function's signature).

But since most users will never change the default cutoffs, I suggest setting the default at the more lenient levels and/or addressing it in the documentation. Do you agree?