Make VCR disallow unexpected HTTP requests.

This makes it so that tests fail when they make HTTP requests they
aren't expected to. Update these tests so that they use VCR like they
should.

test/test_helper.rb

@@ -100,5 +100,5 @@ MEMCACHE = MockMemcache.new
 VCR.configure do |c|
   c.cassette_library_dir = "test/fixtures/vcr_cassettes"
   c.hook_into :webmock
-  c.allow_http_connections_when_no_cassette = true
+  # c.allow_http_connections_when_no_cassette = true
 end

test/unit/downloads/file_test.rb

@@ -27,28 +27,38 @@ module Downloads
       end
 
       should "stream a file from an HTTP source" do
+        VCR.use_cassette("download-file-http", :record => :once) do
           @download.http_get_streaming do |resp|
             assert_equal("200", resp.code)
             assert(resp["Content-Length"].to_i > 0, "File should be larger than 0 bytes")
           end
         end
+      end
 
       should "throw an exception when the file is larger than the maximum" do
         assert_raise(Downloads::File::Error) do
+          VCR.use_cassette("download-file-http", :record => :once) do
             @download.http_get_streaming(:max_size => 1) do |resp|
             end
           end
         end
+      end
 
       should "store the file in the tempfile path" do
+        VCR.use_cassette("download-file-http", :record => :once) do
           @download.download!
+        end
+
         assert_equal(@source, @download.source)
         assert(::File.exists?(@tempfile.path), "temp file should exist")
         assert(::File.size(@tempfile.path) > 0, "should have data")
       end
 
       should "initialize the content type" do
+        VCR.use_cassette("download-file-http", :record => :once) do
           @download.download!
+        end
+
         assert_match(/image\/gif/, @download.content_type)
       end
     end
@@ -65,6 +75,7 @@ module Downloads
       end
 
       should "stream a file from an HTTPS source" do
+        VCR.use_cassette("download-file-https", :record => :once) do
           @download.http_get_streaming do |resp|
             assert_equal("200", resp.code)
             assert(resp["Content-Length"].to_i > 0, "File should be larger than 0 bytes")
@@ -73,3 +84,4 @@ module Downloads
       end
     end
   end
+end

test/unit/upload_test.rb

@@ -104,12 +104,15 @@ class UploadTest < ActiveSupport::TestCase
         should "initialize the final path after downloading a file" do
           @upload = FactoryGirl.create(:source_upload)
           path = "#{Rails.root}/tmp/test.download.jpg"
+
+          VCR.use_cassette("upload-test-file", :record => :once) do
             assert_nothing_raised {@upload.download_from_source(path)}
             assert(File.exists?(path))
             assert_equal(8558, File.size(path))
             assert_equal(path, @upload.file_path)
           end
         end
+      end
 
       context "determining if a file is downloadable" do
         should "classify HTTP sources as downloadable" do