RE: references to `africa' file for zone naming and abbrev. conve ntions.

> A minor nit, but when the zone naming and abbreviation conventions > were moved from tzdata/africa to tzcode/Theory cooresponding cross > references in the comments (See the `africa' file for time zone naming > and abbreviation conventions) comments in other data files were not > updated. Thanks for the catch. I've simply eliminated the cross references to avoid dangling pointers to a "Theory" file that some vendors may not distribute. Folks can expect to see the deletions (or rather not see them) the next time a tzdata archive goes out. --ado