Log Message:
Updated package to the latest version, 8.4pl2. Changes include:

Bug fixes
- Solved bugs :
  #2466 #2629 #2668 #2750 #2839 #2869 #2954 #2955 #2959 #2962 #2966 #2967
  #2969 #2970 #2975 #2976 #2977 #2978 #2981 #2983 #2995 #3000 #3004 #3008
- Partially fixed bugs : #2830 #2949
- Coqtop should now react more reliably when receiving interrupt signals:
  all the "try...with" constructs have been protected against undue
  handling of the Sys.Break exception.

Coqide
- The Windows-specific code handling the interrupt button of Coqide
  had to be reworked (cf. bug #2869). Now, in Win32 this button does
  not target a specific coqtop client, but instead sends a Ctrl-C to
  any process sharing its console with Coqide. To avoid awkward
  effects, it is recommended to launch Coqide via its icon, its menu,
  or in a dedicated console window.

Extraction
- The option Extraction AccessOpaque is now set by default,
  restoring compatibility of older versions of Coq (cf bug #2952).