move git_merge_options changes to correct location

Author: simonbyrne

CHANGELOG.md

@@ -153,6 +153,10 @@ v0.25
 * `git_remote_connect()` now accepts `git_proxy_options` argument, and
   `git_fetch_options` and `git_push_options` each have a `proxy_opts` field.
 
+* `git_merge_options` now provides a `default_driver` that can be used
+  to provide the name of a merge driver to be used to handle files changed
+  during a merge.
+
 v0.24
 -------
 
@@ -228,10 +232,6 @@ v0.24
 
 ### Breaking API changes
 
-* `git_merge_options` now provides a `default_driver` that can be used
-  to provide the name of a merge driver to be used to handle files changed
-  during a merge.
-
 * The `git_merge_tree_flag_t` is now `git_merge_flag_t`.  Subsequently,
   its members are no longer prefixed with `GIT_MERGE_TREE_FLAG` but are
   now prefixed with `GIT_MERGE_FLAG`, and the `tree_flags` field of the