Fix castings objects in parent() and get_children()

The old way didn't work because of the ProcessWrapper and its
delegating to the self._process. It lead to malfunction of the
`_apply_rules` method

tracer/resources/processes.py

@@ -52,6 +52,9 @@ class ProcessWrapper(object):
 	def __init__(self, pid=None):
 		self._process = psutil.Process(pid)
 
+	def __nonzero__(self):
+		return bool(self._process)
+
 	def name(self):
 		return self._attr("name")
 
@@ -118,13 +121,11 @@ def files(self):
 
 		return sorted(files)
 
-	@property
 	def parent(self):
 		"""The parent process casted from ``psutil.Process`` to tracer ``Process``"""
-		p = super(Process, self).parent()
-		if p:
-			p.__class__ = Process
-		return p
+		if self.ppid():
+			return Process(self.ppid())
+		return None
 
 	def username(self):
 		"""The user who owns the process. If user was deleted in the meantime,
@@ -140,9 +141,7 @@ def children(self, recursive=False):
 		"""The collection of process's children. Each of them casted from ``psutil.Process``
 		to tracer ``Process``."""
 		children = super(Process, self).children(recursive)
-		for child in children:
-			child.__class__ = Process
-		return ProcessesCollection(children)
+		return ProcessesCollection([Process(child.pid) for child in children])
 
 	@property
 	def exe(self):

tracer/resources/tracer.py

@@ -105,11 +105,11 @@ def trace_affected(self, user=None):
 		return ApplicationsCollection(affected.values())
 
 	def _apply_rules(self, process):
-		parent = process.parent
+		parent = process.parent()
 		if not parent:
 			return process
 
-		rule = self._rules.find(parent.name)
+		rule = self._rules.find(parent.name())
 
 		if not rule or not rule.action:
 			return process