[BioRuby] Code cleanup: expanded tabs into spaces.

[Anurag Priyam]

I am unsure if it is needed or not. A simple combination of find and sed did
the job.

Here is the one liner that I used:
find . -name '*.rb' -exec sed -i 's/\t/        /g' {} ';'

A patch would have been too long, so I have sent a pull request on github
for review.

Diff:
http://github.com/yeban/bioruby/compare/master...tab

-- 
Anurag Priyam
2nd Year,Mechanical Engineering,
IIT Kharagpur.
+91-9775550642