Replace the source code written in VBScript with JScript

[sdottaka]

This PR rewrites scripts written in VBScript with JScript.
This is because VBScript has been deprecated.
(https://learn.microsoft.com/en-us/windows/whats-new/deprecated-features-resources#vbscript)

VBScript was used a lot in plugins.
This is because it is easier to operate Office applications, it has functions that JScript does not have, such as InputBox, and it is possible to return values with arguments.

The following changes have been made to enable writing plugins in JScript.

• For example, in the Prediffer plugin interface PrediffBufferW, in VBScript, the values were returned using the arguments as shown below.
  In JScript, instead set the values in SAFEARRAY and return it as the return value. (SAFEARRAY can be created via a Dictionary object.)

VBScript

Function PrediffBufferW(text, size, bChanged)
   ...
   text = ...
   size = ...
   bChanged = True
   PrediffBufferW = True
End Function

↓
JScript

function PrediffBufferW(text, size, bChanged) {
   ...
   var result = new ActiveXObject("Scripting.Dictionary");
   result.Add(0, true);
   result.Add(1, text);
   result.Add(2, size);
   result.Add(3, bChanged);
   return result.Items();

• Added InputBox, MsgBox to mergeApp object passed in PluginOnEvent method.