remove files in wrong namespace

fix error with str_singular() helper

fix namespace in document

documents for v2.0.0-alpha4

correct namespace

refactor isDirectory() & pretty() in LfmPath.php

Merge pull request UniSharp#510 from Nikita240/patch-2

Cast the thumbnail object to a string when saving

click on file should call useFile() in grid view

add badge of unstable version number in README

fix psr2