Windows環境でビルドが通るようにした（動作確認は未実施 ）
add "make.bat" for build on Windows
build to "mackerel-agent.exe"
add run.bat and change name make.bat
add README for Windows build and run.
Merge pull request #39 from mackerelio/windows_build

be able to build on windows
care long postDelay
Merge branch 'master' into feature/graceful-shutdown
Merge branch 'feature/refactor-delay' into feature/graceful-shutdown

Conflicts:
	command/command.go