Release 0.9.0 version

This release comes with three new medium features. We now can delay the 1st check for each service in a random way, which reduce the load we may put on the system. Moreover, we now exit the main program when a thread, which is responsible for running the service check, dies due to an unhandled exception or other error. The 3rd functionality allows a user to use a custom command to trigger reconfigure to Bird daemon after a service is marked down or up. This custom command is set per service.

We also ensure, during startup, that variable name in Bird configuration matches the one in our configuration. The lack of this has caused some troubles with configuration management tools(Puppet and etc) under specific circumstances.

Last but not least, we cleaned up and simplified some code.

Changelog:

• Update year in __copyright__
• Simplify conditional statement
• Add support for custom Bird reconfigure per service
• Ensure correct variable name in Bird configuration
• Make docstring more clear
• Simplify return code from a function
• Add docopt in the requires-dist
• More clear log message
• Report information about the lock
• Fix typo in nagios check
• PEP257 compatible docstring for nagios check
• PEP257 compatible docstring for nagios check
• Log stack-trace when a thread dies
• Change the log severity to critical
• Call super in ServiceCheckDiedError
• Rename exception ServiceCheckDied to ServiceCheckDiedError
• Exit main program when a thread dies
• Update Copyright
• Update docstring/comment
• Remove unnecessary coding config
• Add Maximilian Wilhelm to AUTHORS
• Switch to integer for some default values
• Simplify loading default configuration
• Add support for delaying the 1st check
• Fix typo in README
• Rephrase a sentence
• Remove the dependencies to daemon and lockfile
• Disable pylint warnings
• Add configuration for building Debian packages
• Remove unused method _update_status