Update nano to 2.4.3

2015.11.18 - GNU nano 2.4.3 "Apocalypse" is now available for your
downloading pleasure.  This release includes a myriad
of fixes including several memory leaks, issues with
color syntax higlighting, search/replace, file
insertion and help menu bugs.  Many thanks to
Benno Schulenberg for tireless efforts on the vast
majority of fixes for some time now.  As always please
report bugs via the Savannah page, and remember to
Share and Enjoy.

(wiedi)