fix indentation of pre code elements (#1132)
fix indentation of pre code elements (#1132)

Currently there are a number of the guides that have code examples which
have the first code line indented slightly more than the others. This
commit attempts to fix this.
nodejs/new.nodejs.org,yous/new.nodejs.org,nodejs/new.nodejs.org,yous/new.nodejs.org,phillipj/new.nodejs.org,phillipj/new.nodejs.org