Define DiskSpaceCheck class and it's required functions

Modules
		shutil

Classes
		nephos.maintenance.checker.Checker(abc.ABC) DiskSpaceCheck   class DiskSpaceCheck(nephos.maintenance.checker.Checker)     To check if the disk space is less than a minimum threshold defined in config file     Method resolution order: DiskSpaceCheck nephos.maintenance.checker.Checker abc.ABC builtins.object Data and other attributes defined here: __abstractmethods__ = frozenset([]) Methods inherited from nephos.maintenance.checker.Checker: __init__(self, config_maintain) Configures checker for low disk space.   Parameters ---------- config_maintain     type: dictionary     contains information for maintenance task to_run(self, kind) Checks from config file if the maintenance job is to be executed   Parameters ------- kind     type: str     kind of the job to be executed   Returns ------- executes self._executed() if to be executed displays warning log otherwise Data descriptors inherited from abc.ABC: __dict__ dictionary for instance variables (if defined) __weakref__ list of weak references to the object (if defined)

Data
		LOG = <logging.Logger object> __nephos_dir__ = '/home/thealpha/Nephos'