Try to fix Mac again, write version number

resources/ci/common/prepare_appversion.py

@@ -0,0 +1,20 @@
+import common
+import os               # for env vars
+from shutil import copy	# file manipulation
+
+env = common.prepare_env()
+
+# set tag to app_version.txt
+if not env["GITHUB_TAG"] == "":
+  with open(os.path.join(".","resources","app","meta","manifests","app_version.txt"),"w+") as f:
+	  _ = f.read()
+	  f.seek(0)
+	  f.write(env["GITHUB_TAG"])
+	  f.truncate()
+
+if not os.path.isdir(os.path.join("..","build")):
+	os.mkdir(os.path.join("..","build"))
+copy(
+	os.path.join(".","resources","app","meta","manifests","app_version.txt"),
+	os.path.join("..","build","app_version.txt")
+)