Remove a semi-colon
Replace all String#[0] with String#bytes#first

In Ruby 1.8, hi[0] returns h has a byte.
http://ruby-doc.org/core-1.8.7/String.html\#method-i-5B-5D

In Ruby 1.9 and 2.x, #[] returns a slience
http://www.ruby-doc.org/core-2.1.1/String.html\#method-i-5B-5D

All versions respond to #bytes, so this change respresents a
backwards compatible change and bugfix on newer Rubies

closes #5