chore: kemal + crystal setup

spec/spec_helper.cr

@@ -0,0 +1,2 @@
+require "spec"
+require "../src/url-shortener"

spec/url-shortener_spec.cr

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+require "./spec_helper"
+
+describe Url::Shortener do
+  # TODO: Write tests
+
+  it "works" do
+    false.should eq(true)
+  end
+end