Log Message:
Upgrade tkcvs from version 7.0.3 to version 7.1.2.  (Most notable
change, apart from the layout, is that tkdiff is now called tkdiffb).
Summary of changes as follows:

Release 7.1.2
- Fix bugs

Release 7.1.1
- Fix bugs
- Required Tk version is 8.3, not 8.1

Release 7.1
- New functionality, including
- New graphical tool to help with merging directories and seeing an overview
  of the branches.
- New, completely re-written, branching diagram.
- You can invoke the log browser from the command line:
  tkcvs [-dir directory] [-root cvsroot] [-win workdir|module] [-log file]
- Option to use an external editor for commit messages so the rcsinfo template
  feature can be used.
- A picklist keeps a temporary history of directories visited.  Favorite places
  can be bookmarked.
- Capability to browse RCS files, in case you find yourself in an
  rcs-controlled directory.
- A heavily patched TkDiff that works in AquaTK, in case you're a MacOS X fan.
  TkCVS does pretty well in AquaTK as-is, with a few tweaks to tkcvs_def.tcl.
- More intuitive module-operation dialogs contributed by Mike Jagdis.
- Re-arranged buttons.  There's a somewhat overwhelming array, but now almost
  everything is there without resorting to the menus.