Add Support for Ruby 1.9.3

[pca2]

I know you say right up front that only Ruby 1.8 has been tested. I thought it was worth noting that that rdio doesn't work at all in 1.9.3 because there is no 'new' method, which kind of prevents any activity at all. Here's an irb example:

1.9.3p385 :001 > require 'rdio'
=> true 
1.9.3p385 :002 > rdio = Rdio.new
NoMethodError: undefined method `new' for Rdio:Module
    from (irb):2
from /home/carleton/.rvm/rubies/ruby-1.9.3-p385/bin/irb:16:in `<main>'

[alex]

I think this must be an issue with an out of date rdio, looking at the code Rdio is declared as a class (https://github.com/rdio/rdio-simple/blob/master/ruby/rdio.rb#L26) which will automatically have a new method.

[pca2]

Thanks. It looks like the issue is that running "gem install rdio" actually installs the gem located at rdiorb not the official rdiosimple gem. Very confusing for a noob like me.