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Changes

• added multiple new methods to os submodule
• added new methods to os.path submodule
• some methods were moved from os to os.path to be in line with default python implementation
• pathlib.Path has new implementation for most of the methods which should be universally better. Instead of overriding each method it uses Accessor class which in turn relies on methods in os submodule so code is not repeated.
• added ability to use ssh-agents by @lainwir3d this is in early stage and will be enhanced in the future
• shutil submodule also takes advantage of new methods implemented by os
• some methods in os have been simplified

Bugfixes

• multiple unspecified fixes and typos
• the new approach in pathlib.Path means it should be a lot less error prone