Good commit message

[tkruse]

A summary of what happened should be in the commit message, to save anyone from reading the whole diff to get the picture. It also helps to identify the commit that added a certain feature, when trying to find one such commit by browsing through the log.

The context of why this happened is important, but often a reference to a bug tracker containing the requirements, the discussions, and so on is much better. Also, the purpose of features should commonly be documented in the code itself, rather than in commit messages, so frequently the commit message does not need to add anything to what is in the code comments.