Better check if isEditFilenameEnabled

A scenario:
1. Use the same template for editable uploads and noneditable uploads: this._templating.isEditFilenamePossible() will return always true
2. autoUpload set to false: !this._options.autoUpload is always true
3. using the all FineUploader Library: qq.FilenameClickHandler and qq.FilenameInputFocusHandler are always there.

So it seems to be that the name of the file to be uploaded it is always editable (at least in this scenario).