Log the timestamp (date+time) when logging starts

[xsteve]

trafficstars

Hi, I read about your cool module yesterday on python-weekly.

Here is a patch to show the timestamp when logging starts

[xsteve]

I would really love to see my patch merged

[skorokithakis]

I have added a comment, but it looks like a useful feature, so we can merge if @zestyping doesn't have any objections.

[xsteve]

I added my patch a long time ago. Today I found out that there was some activity in this repository. This is why I rebased my pull request to the current master. I use the feature and it is really useful since it shows an entry when I restart my debugged program