Update sites.yml
Update sites.yml
Added a guide helper.

Think it's more appropriate to move sorts done in
'built-using-middleman.html.erb' to a helper in guide_helpers.rb, seemed
repeating.
Minor refactor built-using-middleman.html.erb
Fix typo
Merge pull request #348 from limekin/master

Update sites.yml
Merge pull request #347 from philipjoubert/patch-1

Update sites.yml
Fix typo blogs to blog in built-using-middleman.html.erb
Merge pull request #349 from limekin/master

Fix typo blogs to blog in built-using-middleman.html.erb
Added hint about duplicates
Merge pull request #352 from dg-ratiodata/feature/duplicates_in_build_hint

Added hint about duplicates
Nested layouts `wrap_layout` needs to be outputted

In order for `wrap_layout` to properly work, it needs to be outputted to
using `<%=`. It seems that this is something that recently came about
as it previously was not required. I found this while trying to upgrade
a middleman 3.1 site to 3.3.
Merge pull request #353 from dgalarza/dg-update-nested-layouts

Nested layouts `wrap_layout` needs to be outputted
Added hint about duplicates in JP

related #352
Fix typo
Merge pull request #373 from iliakolev/fix-typo

Fix typo
Revert "Nested layouts `wrap_layout` needs to be outputted"
Merge pull request #376 from middleman/revert-353-dg-update-nested-layouts

Revert "Nested layouts `wrap_layout` needs to be outputted"
Add Level Up and Echobind to sites.

These both happily use Middleman!
Merge pull request #384 from cball/master

Add Level Up and Echobind to sites.