Update __init__.py

Add Windows redist check to client init

syncplay/__init__.py

@@ -3,3 +3,19 @@ revision = ' release candidate 1'
 milestone = 'Yoitsu'
 release_number = '108'
 projectURL = 'https://syncplay.pl/'
+
+def isWindows():
+    return sys.platform.startswith("win")
+
+def doWindowsRedistCheck():
+    import ctypes
+    try:
+        ctypes.CDLL('vcruntime140.dll')
+    except OSError:
+        ctypes.windll.user32.MessageBoxW(0, '''Syncplay relies on the Microsoft Visual C++ Redistributable which is not installed.
+             It can be downloaded at https://aka.ms/vs/17/release/vc_redist.x86.exe
+             For more details see http://syncplay.pl/''', "Syncplay", 1)
+    sys.exit()
+
+if isWindows():
+    doWindowsRedistCheck()