Merge pull request #6799 from Chocobo1/appveyor

Tweak AppveyorCI

.appveyor.yml

@@ -5,6 +5,10 @@ skip_tags: true
 
 os: Visual Studio 2015
 
+branches:
+  except:  # blacklist
+    - coverity_scan
+
 environment:
   REPO_DIR: &REPO_DIR c:\qbittorrent
   CACHE_DIR: &CACHE_DIR c:\qbt_cache
@@ -20,6 +24,8 @@ clone_folder: *REPO_DIR
 cache:
   - *CACHE_DIR
 
+clone_depth: 50
+
 install:
   # check if library needs update
   - appveyor DownloadFile "%QBT_VER_URL%" -FileName "c:\version_new" && SET /P newVersion=<"c:\version_new"