New features in gitk

I just pulled the dev branch of gitk into the master branch, so the master branch now has the new features and improvements that I have been working on, namely:

* The find and highlight functions have been combined into a single
  function, and there is now a button for finding backwards as well as
  a find forwards button.  Thus you can now search for commits that
  modify certain files or directories, or commits that add/remove a
  given string, as well as searching for commits by commit message,
  author, committer or headline.

* Combining the find and highlight functions freed up space that is
  now used for a progress bar and a status window.

* There is now a font chooser accessible from the edit/preferences
  window.

* Gitk now uses a new graph layout algorithm, which means it doesn't
  have to generate the whole layout from top to bottom at startup
  time, making startup faster.  Gitk also uses a new style for drawing
  short diagonal line segments that join an existing vertical line,
  which is visually clearer when the segment crosses another line.

* Gitk caches the topology information used for the previous/next tag
  and branch information, making startup faster.

Tk 8.5 is now in beta, meaning that some distros now have it packaged. Gitk looks much nicer in Tk8.5 since it supports anti-aliased fonts, so I strongly suggest that people install and use Tk8.5 if possible.

Paul.