New data format is broken for vimproc#readdir()

[Shougo]

#206 is broken.

Test case:

• Create empty directory.

$ mkdir -p test/test/test

• Get files by vimproc#readdir()

:echo vimproc#readdir('test/test'), :echo vimproc#readdir('test/test/test')

• vimproc#readdir('test/test/test') got "test/test/test" file...

[k-takata]

Sorry, fixed.
The previous result was returned when a directory was empty.

[Shougo]

Thank you!