Fix printing package manager name in --show-resource=system

Now when we use PackageManger adapter, we can't just print
its name, but names of all managers that it use

tracer/controllers/resource.py

@@ -81,11 +81,11 @@ def render_system(self):
 
 		users = set([user.name for user in psutil.get_users()])
 		user = os.getlogin()
-		package_manager = System.package_manager().__class__.__name__
+		package_managers = System.package_manager().names()
 
 		view = SystemView()
 		view.assign('distribution', System.distribution())
-		view.assign('package_manager', package_manager)
+		view.assign('package_managers', package_managers)
 		view.assign('init', System.init_system())
 		view.assign('uptime', uptime)
 		view.assign('user', user)

tracer/resources/PackageManager.py

@@ -37,6 +37,9 @@ class PackageManager:
 	def __init__(self, *instances):
 		self.package_managers = instances
 
+	def names(self):
+		return map(lambda x: x.__class__.__name__ ,self.package_managers)
+
 	def packages_newer_than(self, unix_time):
 		"""
 		Returns list of packages which were modified between unix_time and present

tracer/views/resource/system.py

@@ -5,7 +5,7 @@ class SystemView(View):
 	def render(self):
 		line = "{0:<20}{1}"
 		print line.format("Distribution:", self.args.distribution)
-		print line.format("Package Manager:", self.args.package_manager)
+		print line.format("Package Manager:", ", ".join(self.args.package_managers))
 		print line.format("Init system:", self.args.init)
 		print line.format("Uptime:", self.args.uptime)
 		print line.format("User:", self.args.user)