added apispark extension page and inserted its line in editions matrix
changed login to userName and security token to secret key for consistency with names in APISpark UI
Update apispark.md

Replaced acronyms
Update apispark.md

Removed features that aren't available in preview
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remembered readers they need to be authenticated to access their user tokens
Update index.html

Updated front page
Update apispark.md

Changed command line help to add the d parameter that will enable people to update the def
Updated images

New Restlet logo and header background
Update styles.css

Updated header background image.
Update footer.ftl

Updated main logo.
Update styles.css

Updated color of the border (under the header).
Update index.html

Added GitHub "Star" button.
Update apispark.md
Update apispark.md
Update apispark.md
Update apispark.md

Added image as requested by JLO in ticket #943
added overview image of injected resource
Merge branch 'RFTicket943' of github.com:restlet/restlet-sites into RFTicket943
Update apispark.md

Added slash at the end of URL
Integrate Mixpanel funnel