HGitaly: separate log file
Similar to what has been done in HDK and foss.h.n, because it is useful to be able to set HGitaly logs to DEBUG
whereas the debug logs of Mercurial core are usually irrelevant in our context.
Similar to what has been done in HDK and foss.h.n, because it is useful to be able to set HGitaly logs to DEBUG
whereas the debug logs of Mercurial core are usually irrelevant in our context.