Make CI run the profile task(s)

[dentarg]

We only have profile:normalize for now,

twingly-url/Rakefile

Lines 3 to 14 in 11c4908

	namespace :profile do
	require_relative "profile/profile"
	desc "Profile"
	task :normalize do |task|
	require_relative "lib/twingly/url"
	Profile.measure "normalizing a short URL", 1000 do
	Twingly::URL.parse('http://www.duh.se/').normalized
	end
	end
	end

The tasks produces HTML files (can be seen in #69), not sure about console output, but hopefully there is some result printed to the console, or we can make it print some, so this is useful to run on Travis :)