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- PidFile will now look at the environment variables it
needs just before acquiring the lock instead of at
instantiation time of the PidFile class.
- pid is now friendly with daemon context managers such
as python-daemon where the PidFile context manager is
passed as a parameter.
- The signal handler on SIGTERM is now only installed
automatically if there is no previous signal handler
installed.
- You can install a custom SIGTERM handler by specifying
a callable for 'register_term_signal_handler'.
- All in all we tried to make sure that with version 2.0.0
pid will play nice with other code and has sane defaults.
- Many thanks to nnathan who's efforts coding and testing
made this version possible.