Allow selecting image type via Regexp

For example, SVG images might be of type "image/svg" or "image/svg+xml"

lib/manifique/metadata.rb

@@ -43,7 +43,13 @@ module Manifique
       end
 
       if options[:type]
-        results.reject! { |r| r["type"] != options[:type] }
+        if options[:type].is_a?(String)
+          results.reject! { |r| r["type"] != options[:type] }
+        elsif options[:type].is_a?(Regexp)
+          results.reject! { |r| r["type"].match(options[:type]).nil? }
+        else
+          raise ArgumentError, "Type must be a string or a regular expression"
+        end
       end
 
       if options[:sizes]

spec/manifique/metadata_spec.rb

@@ -68,6 +68,16 @@ RSpec.describe Manifique::Metadata do
         icon = metadata.select_icon(type: "image/png")
         expect(icon["sizes"]).to eq("512x512")
       end
+
+      it "matches strings exactly" do
+        icon = metadata.select_icon(type: "image/svg")
+        expect(icon["type"]).to eq("image/svg")
+      end
+
+      it "works with a regex" do
+        icon = metadata.select_icon(type: /image\/svg/)
+        expect(icon["type"]).to eq("image/svg+xml")
+      end
     end
 
     describe "by size" do