Fix lsi.rb Comparable#== warning
Fix lsi.rb Comparable#== warning

Warnings produced when doing `jekyll build` were:

warning: Comparable#== will no more rescue exceptions of #<=> in the next release.
warning: Return nil in #<=> if the comparison is inappropriate or avoid such comparison.

The warnings are supressed when using .eql? method.

jekyll (2.5.3)
classifier-reborn (2.0.3)
rb-gsl (1.16.0.4)

kreynolds/classifier-reborn,MadBomber/classifier-reborn,MadBomber/classifier-reborn,sanbiv/classifier-reborn,kreynolds/classifier-reborn,jekyll/classifier-reborn,jekyll/classifier-reborn,sanbiv/classifier-reborn