Quick fix for cut-off navigation

The better alternative would be to have the "Back To Top" button fixed to the top, and the rest of the side nav scrolling.
Add some tips for running Vagrant in Common Issues section
Update docs with `included` addon hook

Includes a brief demonstration of using `included` to inject your
own preprocessor into the app or parentAddon.
Move upgrading info to it's own section
Add explanation of wrapEval, fix typo
Merge pull request #2436 from t3hmrman/gh-pages

Add explanation of wrapEval, fix typo
Added space suggested on PR #2436
Use highlight helper for unsafe-eval section code
Merge pull request #2444 from t3hmrman/gh-pages

Fix code element in new unsafe eval section
Merge pull request #2355 from knownasilya/patch-7

Quick fix for cut-off navigation
Update 2013-04-06-developing-addons-and-blueprints.md
Merge pull request #2448 from dennismende/patch-1

Update 2013-04-06-developing-addons-and-blueprints.md
Add outputPaths explanation and documentation #1888
Adjust podModulePrefix example to be less confusing
Merge pull request #2509 from peterchoo/gh-pages

Adjust podModulePrefix example to be less confusing
Merge pull request #2477 from tstirrat/outputPaths-docs

[DOCS] Output path configuration documentation
Merge pull request #2427 from HeroicEric/gh-pages

[DOCS] Move upgrading info to it's own section
Merge pull request #2382 from davewasmer/gh-pages

Update docs to mention `included` addon hook
Merge pull request #2380 from zackangelo/docs-vagrant-tips

Add some tips for running Vagrant in Common Issues section
Clarifies the subject of this post

* Previously mentioned only modules in the title but also explains
* the Resolver