downcase lexers before passing to Pygments
actually downcase lexer
test for lexer case insensitivity
Add test to reflect #1622 behaviour
Add support for use of folders inside _layout path, closes #1622
Add cucumber feature for layouts inside subfolders
jekyll-import warning note of missing deps.

The jekyll-import gem, opted to leave out importer-specific runtime dependencies. I'm adding a warning note for the user to be aware of this and manually install the ones they need based on the importer they are using.
Fix typos.
Show the complete name and no abbreviation.
requieres.
Merge pull request #1622 from blackjid/master

enable the use of folders inside the _layout path
Update history to reflect merge of #1622
Merge pull request #1615 from benbalter/downcase-lexers

Downcase lexers before passing to Pygments
Update history to reflect merge of #1615
Update history to reflect merge of #1614
Fix typos.
Merge pull request #1626 from albertogg/migrations-warning-note

jekyll-import warning note of missing deps.
Update history to reflect merge of #1626