export new 2l.logit function
Eliminate duplicates from collation sequence in DESCRIPTION,
and fix .r/.R mismatches with actual file names.
The package is now installable, though with complaints:

** preparing package for lazy loading
in method for 'cci' with signature 'x="mids"': no definition for class "mids"
in method for 'ici' with signature 'x="mids"': no definition for class "mids"
Merge branch 'master' of https://github.com/RossBoylan/mice
I think this includes my cleanup (done locally) to collate field
in DESCRIPTION
Conflicts:
	DESCRIPTION
	R/mice.R
	inst/NEWS
Merge branch 'master' into multilevel.
The idea was to pick up the new, sensible collate field in DESCRIPTION, but
it seems I mostly had it.
This diff also appears to add mice.impute.2l.nonlinear.r to the collate
field, which is weird since I already added it.

Conflicts:
	DESCRIPTION
	inst/NEWS