Merge branch 'master' into 3.0

# Conflicts:
#	dev-requirements.txt
#	gns3server/controller/__init__.py
#	gns3server/controller/appliance_manager.py
#	gns3server/controller/compute.py
#	gns3server/controller/topology.py
#	gns3server/handlers/api/compute/ethernet_switch_handler.py
#	gns3server/handlers/api/controller/link_handler.py
#	gns3server/handlers/api/controller/symbol_handler.py
#	gns3server/version.py
#	requirements.txt
#	tests/controller/test_export_project.py
#	tests/handlers/api/compute/test_qemu.py
#	tests/web/test_response.py
#	win-requirements.txt

gns3server/controller/appliance_manager.py

@@ -16,6 +16,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
+import shutil
 import json
 import uuid
 import asyncio
@@ -181,6 +182,7 @@ class ApplianceManager:
                     Controller.instance().save()
                 json_data = await response.json()
             appliances_dir = get_resource('appliances')
+            downloaded_appliance_files = []
             for appliance in json_data:
                 if appliance["type"] == "file":
                     appliance_name = appliance["name"]
@@ -201,6 +203,21 @@ class ApplianceManager:
                                 f.write(appliance_data)
                         except OSError as e:
                             raise ControllerError("Could not write appliance file '{}': {}".format(path, e))
+                        downloaded_appliance_files.append(appliance_name)
+
+            # delete old appliance files
+            for filename in os.listdir(appliances_dir):
+                file_path = os.path.join(appliances_dir, filename)
+                if filename in downloaded_appliance_files:
+                    continue
+                try:
+                    if os.path.isfile(file_path) or os.path.islink(file_path):
+                        log.info("Deleting old appliance file {}".format(file_path))
+                        os.unlink(file_path)
+                except OSError as e:
+                    log.warning("Could not delete old appliance file '{}': {}".format(file_path, e))
+                    continue
+
         except ValueError as e:
             raise ControllerError("Could not read appliances information from GitHub: {}".format(e))