fix msvc warnings
add a test of fs::STAT_SIZE
fix wrong times of fs::Stats
use uv_statbuf_t
update submodule 'libj'
rename appendCStr to appendStr
update submodule 'libj'
use unsignedToString and appendStr
uninclude windows.h
add submodule 'gflags'
update submodule 'libj'
update submodule 'gflags'
build gflags
use deps/gflags
exclude example/deps
exclude example/deps
add the license description of example/deps/gflags
update submodule 'gflags'
remove redundant String::valueOf
introduce LIBJ_U