[makeotf] Fix '-cn' option

[miguelsousa]

Fixes makeotf's option that converts the OTF's CFF (name-keyed) table to a CID-keyed CFF table.
Also took the opportunity to do other small fixes and clean-ups.
Fixes #470

[cjchapman]

The two problems below are not in the section you changed, but since you're doing this level of cleanup, I think it would be good to fix these (and to make sure we have a test that hits this code, as apparently we don't):

This call in ufotools.py, starting at line 1007 is wrong:

                fdGlyphDict, fontDictList, finalFDict = \
                    convertfonttocid.parseFontInfoFile(
                        fontDictList, fontInfoData, glyphList,
                        maxY, minY, psName, blueFuzz)

parseFontInfoFile() doesn't take so many arguments, I think the fontDictList is the spurious one.

Also, this code in ufotools.py starting at line 1017 is wrong:

                    convertfonttocid.mergeFDDicts(
                        [finalFDict], self.topDict)

as topDict is not defined anywhere.

[miguelsousa]

ufotools.UFOFontData.getfdInfo() seem to be used by autohint and stemhist.
I've opened #531 to address those fixes separately from this PR.