Latest update of locales introduced abbreviated month that follows the regionale
rules meaning that they can be of variable length instead of being arbitrary
truncated to top 3 characters.
To fix alignement, ls now computes the visible length of the abbreviated month,
pads the shorter month with spaces in order to make sure everything is properly
aligned
Reviewed by: ache, ed, jilles
Differential Revision: https://reviews.freebsd.org/D4239
be90c1c6b5