* (bug 30977) Remove directions cruft, undo random limitation of input format for...

* (bug 30977) Remove directions cruft, undo random limitation of input format for Special:Filepath

Reverts r43471 which forced Special:FilePath's input to not accept titles with the File: or Image: namespace on them, or otherwise requiring any normalization beyond space/underscore.
Also removes the extra line saying 'input the name without the file: prefix' which used the native namespace name, which prompted a question about its formatting in mixed-directionality contexts.