Removed superfluous repetition and redundancy in titles

There's a lot of this sort of thing all over the guides, and I removed
them where appropriate:

Before:

![before](http://f.cl.ly/items/2c1S1F2c36030H3U1e2A/stork.jpg)

After:

![after](http://f.cl.ly/items/0Z3w2N3f0L1k1c3r2v1d/nork.jpg)
Merge pull request #670 from machty/dry-dry-dry-dry-dry

Removed superfluous repetition and redundancy in titles