Change debug.log from UTC to localtime. Fixes #3872.

I don't know if we actually want to change this, just preparing a commit just in case. We also may want to add a ISO 8601 +02:00 type thing, but I'm yet to work that out. I've tested and it seems localtime gives that same type of output as gmtime.

<b>EDIT: Do Not Merge! Creates wrong behaviour in `EncodeDumpTime` which relies on this being UTC.</b>