Scroll console panel to bottom when new content is added

[imagejan]

This is my take on fixing issue #7

[ctrueden]

Thanks! Unfortunately, in my tests, there are a couple of problems:

• The console does not quite scroll to the very bottom.
• The console jumps to the bottom regardless of the position of the scroll bar. Better would be to only keep things scrolled to the bottom if the scroll bar is already at the bottom. This is how most popular terminal applications work.

I pushed an alternative fix: ad58bd7
Which uses new utility methods: a6d8604