libgit2 v1.4.1

🐞 This is a bugfix release with the following changes:

• xdiff: use xdl_free not free by @ethomson
• cmake: Fix package name for system http-parser by @mgorny
• Free parent and ref in lg2_commit before returning by @apnadkarni

All users of the v1.4 release line are recommended to upgrade.

Full Changelog: v1.4.0...v1.4.1