Update kaleidoscope.gemspec

[dpsk]

kaleidoscope at /Users/dpsk/.rvm/gems/ruby-2.1.1@colorsearch/bundler/gems/kaleidoscope-39198d02ef3c did not have a valid gemspec. This prevents bundler from installing bins or native extensions, but that may not affect its functionality. The validation message from Rubygems was: duplicate dependency on rails (>= 0, development), (>= 4.0.0) use: add_runtime_dependency 'rails', '>= 0', '>= 4.0.0'