added object_input_asset_tag function for using sfMediaLibrary within admin generated edit views
added object_input_asset_tag function for using sfMediaLibrary within admin generated edit views

git-svn-id: bb9470e39291a37d234e515de1aa38e4e0611237@4820 ee427ae8-e902-0410-961c-c3ed070cd9f9

yevgenko/w3s_media_library_plugin,yevgenko/w3s_media_library_plugin