send ico files with inline disposition

app/uploaders/uploader_helper.rb

 # Extra methods for uploader
 module UploaderHelper
-  IMAGE_EXT = %w[png jpg jpeg gif bmp tiff].freeze
+  IMAGE_EXT = %w[png jpg jpeg gif bmp tiff ico].freeze
   # We recommend using the .mp4 format over .mov. Videos in .mov format can
   # still be used but you really need to make sure they are served with the
   # proper MIME type video/mp4 and not video/quicktime or your videos won't play

spec/models/group_spec.rb

@@ -240,7 +240,7 @@ describe Group do
 
     it "is false if avatar is html page" do
       group.update_attribute(:avatar, 'uploads/avatar.html')
-      expect(group.avatar_type).to eq(["file format is not supported. Please try one of the following supported formats: png, jpg, jpeg, gif, bmp, tiff"])
+      expect(group.avatar_type).to eq(["file format is not supported. Please try one of the following supported formats: png, jpg, jpeg, gif, bmp, tiff, ico"])
     end
   end
 

spec/models/project_spec.rb

@@ -960,7 +960,7 @@ describe Project do
 
     it 'is false if avatar is html page' do
       project.update_attribute(:avatar, 'uploads/avatar.html')
-      expect(project.avatar_type).to eq(['file format is not supported. Please try one of the following supported formats: png, jpg, jpeg, gif, bmp, tiff'])
+      expect(project.avatar_type).to eq(['file format is not supported. Please try one of the following supported formats: png, jpg, jpeg, gif, bmp, tiff, ico'])
     end
   end
 

spec/models/user_spec.rb

@@ -1260,7 +1260,7 @@ describe User do
     it 'is false if avatar is html page' do
       user.update_attribute(:avatar, 'uploads/avatar.html')
 
-      expect(user.avatar_type).to eq(['file format is not supported. Please try one of the following supported formats: png, jpg, jpeg, gif, bmp, tiff'])
+      expect(user.avatar_type).to eq(['file format is not supported. Please try one of the following supported formats: png, jpg, jpeg, gif, bmp, tiff, ico'])
     end
   end