Adding fake_hybrid2
Adding Nbc.random_winner_max_index.
Adding initial support for all-rank NBC.
Merge remote-tracking branch 'local/multirank-nbc' into 290-nbc-ties
Fixing seeded NBC support.
Merge remote-tracking branch 'local/multirank-nbc' into 290-nbc-ties
Allowing multiclassification to be disabled.

If the provided multiclass-min is less than 0, multiclassification is disabled.
Merge remote-tracking branch 'local/multirank-nbc' into 290-nbc-ties
adding a random tie-breaking option
Merge branch '290-nbc-ties' of github.com:matsen/pplacer into 290-nbc-ties

Conflicts:
	pplacer_src/nbc.mli
clarifying comments about setting rank to be "all"
Provide --nbc-sequences and --no-pre-mask when using classifier
Merge branch '290-nbc-ties' of git://github.com/matsen/pplacer into 290-nbc-ties
prevent duplicate --no-pre-mask
Merge branch 'dev' into 290-nbc-ties

Conflicts:
	pplacer_src/nbc.ml
	pplacer_src/nbc.mli

Some hand-mangling was needed.
fix for merge function signature change