Delete ChangeLog

It’s been discontinued for almost a decade, so time to clean up.

ChangeLog

@@ -1,32 +0,0 @@
-=== ChangeLog discontinued ===
-
- libsecret relies on commit messages to provide change history. Please
- write commit messages in the following format:
-
-=== begin example commit ===
-
- Short explanation of the commit
-
- Longer explanation explaining exactly what's changed, whether any
- external or private interfaces changed, what bugs were fixed (with bug
- tracker reference if applicable) and so forth. Be concise but not too
- brief.
-
-=== end example commit ===
-
- - Always add a brief description of the commit to the _first_ line of
- the commit and terminate by two newlines. This may be the title of
- a fixed bug, copied from Bugzilla.
-
- - First line (the brief description) must only be one sentence and
- should start with a capital letter unless it starts with a
- lowercase symbol or identifier. Don't use a trailing full stop,
- and don't exceed 72 characters.
-
- - The main description (the body) is normal prose and should use
- normal punctuation and capital letters where appropriate.
-
- - When committing code on behalf of others use the --author option,
- e.g. git commit -a --author "Joe Coder <joe@coder.org>" and
- --signoff.
-