Rubocop: lib/blast.rb, refactor

Signed-off-by: Vivek Rai <vivekraiiitkgp@gmail.com>
pp_hsp would calculate alignment start width incorrectly sometimes. Fix it.

Signed-off-by: Anurag Priyam <anurag08priyam@gmail.com>
Merge remote-tracking branch 'vivek/master' into next

* vivek/master:
  Rubocop: lib/blast.rb, refactor

Signed-off-by: Anurag Priyam <anurag08priyam@gmail.com>