Mirakuru

=====

- [bugfix] atexit cleanup_subprocesses() function now reimports needed functions

=====

- [bugfix] Handle IOErrors from psutil (112)
- [bugfix] Pass global vars to atexit cleanup_subprocesses function (111)

=====

- [feature] Kill all running mirakuru subprocesses on python exit.
- [enhancement] Prefer psutil library (>=4.0.0) over calling 'ps xe' command to find leaked subprocesses.

=====

- [feature] HTTPExecutor enriched with the 'status' argument.
It allows to define which HTTP status code(s) signify that a HTTP server is running.
- [feature] Changed executor methods to return itself to allow method chaining.
- [feature] Context Manager to return Executor instance, allows creating Executor instance on the fly.
- [style] Migrated `%` string formating to `format()`.
- [style] Explicitly numbered replacement fields in string.
- [docs] Added documentation for timeouts.

=====

- [refactoring] Moved source to src directory.
- [fix, feature] Python 3.5 fixes.
- [fix] Docstring changes for updated pep257.

=====

- [fix] Modify MANIFEST to prune tests folder.
- [feature] HTTPExecutor will now set the default 80 if not present in a URL.
- [feature] Detect subprocesses exiting erroneously while polling the checks and error early.
- [fix] Make test_forgotten_stop pass by preventing the shell from optimizing forking out.