Change the behavior of the reset

Change the behavior of the reset

The reset restarts the 64bit process. This avoids the reset can't
cause any effect on the 64bit applications.

This commit includes the following changes.
- Make CMainFrame::TerminatePollThread wait until the thread really
  terminates.
- Make SendIPC64Message and IsWow64 in CXkeymacsApp static methods.
- Make IsWow64 invoke always IsWow64Process, remove the invocation
  from Start64bitProcess, and add Terminate64bitProcess in CXkeymacsApp.
- Delete InitDllData and make SetDllData public in CProfile.
- Remove IPC64_RESET of an IPC message.
- Change CMainFrame::OnReset as above.