Search all view paths for mobile view templates

現在 `include Jpmobile::ViewSelector` した場合に Jpmobile のロジックでビューを決定するために使われるのは Rails.root/app/views のみハードコードされており、エンジンを使っているなどにより他の箇所にビューテンプレートが置かれている場合に検索されません。

このパッチでは `include Jpmobile::ViewSelector` したタイミングで見えている `view_paths` をもとに `Jpmobile::Resolver` を複数生成するようにしてみました。

パッチ適用前

    Started GET "/test_engine/articles/" for 127.0.0.1 at 2013-04-13 12:07:32 +0900
    Processing by TestEngine::ArticlesController#index as HTML
    [TestEngine]
      Rendered test_engine/app/views/test_engine/articles/index.html.erb within layouts/test_engine/application (1.2ms)
    Completed 200 OK in 9ms (Views: 8.9ms)
    
    Started GET "/test_engine/articles/" for 127.0.0.1 at 2013-04-13 12:07:38 +0900
    Processing by TestEngine::ArticlesController#index as HTML
    [TestEngine] #<Jpmobile::Mobile::Iphone:0x007fb4db4d3ea0>
      Rendered test_engine/app/views/test_engine/articles/index.html.erb within layouts/test_engine/application (0.3ms)
    Completed 200 OK in 4ms (Views: 3.3ms)

    Started GET "/test_engine/articles/" for 127.0.0.1 at 2013-04-13 12:07:49 +0900
    Processing by TestEngine::ArticlesController#index as HTML
    [TestEngine] #<Jpmobile::Mobile::Docomo:0x007fb4dac70330>
      Rendered test_engine/app/views/test_engine/articles/index.html.erb within layouts/test_engine/application (0.4ms)
    Completed 200 OK in 5ms (Views: 4.6ms)

パッチ適用後


    Started GET "/test_engine/articles/" for 127.0.0.1 at 2013-04-13 12:10:36 +0900
    Processing by TestEngine::ArticlesController#index as HTML
    [TestEngine]
      Rendered test_engine/app/views/test_engine/articles/index.html.erb within layouts/test_engine/application (1.0ms)
    Completed 200 OK in 8ms (Views: 7.5ms)
    
    
    Started GET "/test_engine/articles/" for 127.0.0.1 at 2013-04-13 12:10:43 +0900
    Processing by TestEngine::ArticlesController#index as HTML
    [TestEngine] #<Jpmobile::Mobile::Iphone:0x007f84345dea48>
      Rendered test_engine/app/views/test_engine/articles/index_smart_phone.html.erb within layouts/test_engine/application (0.4ms)
    Completed 200 OK in 6ms (Views: 5.6ms)
    
    
    Started GET "/test_engine/articles/" for 127.0.0.1 at 2013-04-13 12:10:51 +0900
    Processing by TestEngine::ArticlesController#index as HTML
    [TestEngine] #<Jpmobile::Mobile::Docomo:0x007f84323fe248>
      Rendered test_engine/app/views/test_engine/articles/index_mobile.html.erb within layouts/test_engine/application (0.4ms)
    Completed 200 OK in 5ms (Views: 5.1ms)