add and style split API buttons to header.
Merge branch 'master' into design/39-split-api-button
fix link to api summary, also fix some minor coding standards issues
convert <a> to <Link>, fix some minor coding standards issues, remove classes for github icon
use logo mark from config, if provided - also fix some minor coding standards issues
Merge branch 'master' into design/39-split-api-button
refactor and restyle api-summary link and external api link in header
Merge pull request #39 from synapsestudios/design/39-split-api-button

Split link for back arrow and api name into two links