ChangeLog housekeeping.

Archive old `ChangeLog` file.

We no longer write ChangeLog entries manually; instead, the file will be
created from commit messages (which should be formatted in GNU's ChangeLog
style) by a call to

  gitlog-to-changelog --format='%B%n'

or something similar (this script is part of the 'gnulib' repository).

.gitattributes

@@ -1 +0,0 @@
-ChangeLog       merge=merge-changelog

README.git

@@ -72,26 +72,6 @@ to execute `autogen.sh`  in advance; this script clones  the 'dlg' git
 submodule and copies some files into FreeType's source tree.
 
 
-contributing
-------------
-
-If you want to contribute to FreeType it is recommended to install the
-`git-merge-changelog` program – we use a `ChangeLog` file, which often
-prevents   simple   merging   due  to   conflicts.    Most   GNU/Linux
-distributions  have a  package  for this  program;  otherwise you  can
-install it via the 'gnulib' git repository.  Detailed instructions can
-be found at the beginning of
-
-  https://git.savannah.gnu.org/cgit/gnulib.git/tree/lib/git-merge-changelog.c
-
-To make  it actually work, add  to file `.git/config` in  the FreeType
-git repository (or to your `$HOME/.gitconfig` file) the lines
-
-  [merge "merge-changelog"]
-     name = GNU-style ChangeLog merge driver
-     driver = /usr/local/bin/git-merge-changelog %O %A %B
-
-
 ----------------------------------------------------------------------
 
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