switch to Module::Build
remove patch feature and depends Time::Piece 1.20
remove Test::LoadAllModules
fix caller
Merge remote-tracking branch 'origin/remove_patch' into remove_patch
ignore blib
Merge pull request #4 from takuji31/remove_patch

remove code of caring old Time::Piece and now Time::Piece::Plus depend on Time::Piece 1.20 or later.