only add versions on Windows

The version-file property only has any effect on Windows.

make_installer.py

@@ -1,13 +1,13 @@
 import PyInstaller.__main__
 import os
+import sys
 
 os.system("git -C . describe --match \"*.*.*\" --tags > version.txt")
 
-PyInstaller.__main__.run([
+arguments = [
     'krowlog.py',
     # '--onefile',
     '--noconfirm',
-    '--version-file=version.py',
     '--name=krowlog',
     '--windowed',
     '--icon=icons' + os.sep + 'krowlog.ico',  # doesn't work on Linux (needs .desktop file), windows needs ico
@@ -22,4 +22,9 @@ PyInstaller.__main__.run([
     '--hidden-import=watchdog.observers',
     '--hidden-import=watchdog.version',
     '--hidden-import=configparser'
-])
+]
+
+if sys.platform == 'win32' or sys.platform == 'cygwin':
+    arguments.append('--version-file=version.py')
+
+PyInstaller.__main__.run(arguments)