change in behavior in data.table 1.9.4 unique caused failing tests
(cherry-picked 87866bd, 8559bf4, ce790f2)

Conflicts:
	R/AllClasses.R
	R/SingleCellAssay-methods.R
	R/lmWrapper-bayesglm.R
	inst/tests/test-lmWrapper-bayesglm.R
docs regenerated by roxygen4.0.2