Catch any errors raised by main()

Previously if main() had raised some kind of error then the
application would exit without calling PAUSE on windows. Then
the user wouldnt be able to read the error message.

electrumpersonalserver/server/common.py

@@ -505,7 +505,10 @@ def rescan_script(logger, rpc, rescan_date):
 
 if __name__ == "__main__":
     #entry point for pyinstaller executable
-    res = main()
+    try:
+        res = main()
+    except:
+        res = 1
 
     # only relevant for pyinstaller executables (on Windows):
     if os.name == 'nt':