Console output update

Updates Jenkins' console output with several new nice styles:

- Console output background is now black (more terminal-esque feel)
- Font size increased for readability
- Removes Courier New from default fixed-width font list, adds Consolas, Menlo instead.

Before:

<img src="https://api.monosnap.com/image/download?id=LbknPdixnzT0Tz4tJUjLz6rS5Tr4y3" />

After:

<img src="https://api.monosnap.com/image/download?id=WJPBYdJPA0YIa2YWx0L4c9kkd1FHWF" />