Log Message:
devel/difftastic: update to 0.60.0

Diffing
 - Fixed a crash (introduced in 0.59) when the final changed hunk included the \ 
last line of the file.

Display
 - Fixed an issue where files with no common content would show duplicate hunks.
 - Fixed a performance issue when files had extremely long lines (e.g. 100,000+ \ 
characters).