fixed ServerEngine.create
Daemon: added :daemonize_error_exit_code option
ProcessManager: updated default values; immediate_kill_timeout = -1 means no timeout
v1.5.2
README.md: updated examples
fixed license applying
added license= to gemspec
fixed a typo
Merge pull request #3 from sonots/typo

fixed a typo on README
Daemon uses Process::UID.from_name and Process::GID.from_name to get uid or gid
fixed license application
worker_type=thread calls before_fork
added MultiWorkerServer#join_workers
fixed DaemonLogger::initialize to use config[:log_level]
v1.5.3