Edited equation_of_time. Separating the tropical and anomalous portions provided several more bits to work with.

git-svn-id: http://svn.savannah.nongnu.org/svn/avr-libc/trunk@2336 1084037a-409f-4a99-8160-1a4b3577d4c1
Fixed an error computing the fractional day.

git-svn-id: http://svn.savannah.nongnu.org/svn/avr-libc/trunk@2337 1084037a-409f-4a99-8160-1a4b3577d4c1
Fixed a typo in eu_dst(). 

git-svn-id: http://svn.savannah.nongnu.org/svn/avr-libc/trunk@2338 1084037a-409f-4a99-8160-1a4b3577d4c1