Merge pull request #265 from chrisyue/master

`nc` support trait
Ruby `pry` snippet inserts only one line

Problem: pry snippet inserts 2 lines instead of one. The other line is
used as a document header margin (for source code readability).
Merge pull request #267 from bsutic/ruby-pry-fix

Ruby `pry` snippet inserts only one line
add symfony2 DataTransformer and EventSubscriber