tkdiff Code

* CRITICAL bug that MIGHT corrupt merge results (from Split/Combine)
by embedding extra copies of adjacent lines was eliminated.
* ReIMPLEMENTED the 3way diff support to properly assign merge sides
- Initial choices are now chosen to preserve ancestral modifications
- Markers denoting lines contributing to any ancestor-based decision
making are now displayed when run in 3way mode.
- The 'predominate' merge choice default (ie. users choice of side)
is NOW always subordinate to any ancestor-derived choices
- "Simple" collision resolutions can result in its highlight removal
This includes 'picking' a side, or possibly by Splitting the region
- Provided status msgs (to a popup), in lieu of a busy cursor, at pgm
startup w/SCM use to account for potential network latency delay
- Help info refined to describe 3way support, displays & latency
* Random bugs repaired
- Collision color in the DiffMap now honors its preference value
- The DiffMap is redrawn as needed for Split/Combine and/or collisions
- Misleading (inactive) filelist per-file 'menu accelerators' removed
- Avoids crash (chooses line 1) when no CDR exists and invoking Editor
- Report Save-as filename browser was lacking users filetype choices

"tag_copy_by_TkSVN"

"tag_copy_by_TkSVN"

"tags_directory_path_by_TkSVN"

Tag 4.3.1 release r122

"Removed_using_TkSVN"

This should be r122

"tag_copy_by_TkSVN"

"tags_directory_path_by_TkSVN"

* Fixed obtuse but fatal data-related crash (inline-diffing IDENTICAL lines)
* NewDiff dialog modified to include missing "-1/-2 param" from cmdline and
more useful resize handling in its "More" option subwindow.
* silly typos in help info repaired