Remove old versions when updating package

WAPT/control

@@ -1,5 +1,5 @@
 package           : fws-tortoisegit
-version           : 2.7.0.0-1
+version           : 2.7.0.0-2
 architecture      : all
 section           : base
 priority          : optional

setup.py

@@ -22,11 +22,15 @@ def update_package():
     pe = PackageEntry();
     control = pe.load_control_from_wapt('.')
     for arch in ['32','64']:
-        if not isfile('TortoiseGit-%s.0-%sbit.msi' % (version, arch)):
         filename = 'TortoiseGit-%s.0-%sbit.msi' % (version, arch)
         url = 'https://download.tortoisegit.org/tgit/%s.0/%s' % (version, filename)
+        if not isfile('TortoiseGit-%s.0-%sbit.msi' % (version, arch)):
             print('Downloading Tortoise Git %s for win%s from %s' % (version, arch, url))
             wget(url, filename)
+        if isfile(filename):
+            for old in glob.glob(r'TortoiseGit-*%sbit.msi' % arch):
+                if old != filename:
+                    remove_file(old)
 
     if Version(version) > Version(control['version'].split('-',1)[0]):
         print('Updating control file with new version %s' % version)