Update workshop-map.svg

Added links with: +   xmlns:xlink="http://www.w3.org/1999/xlink
and ...
perl -ne 's/\>(.*)<\/tspan>/>\<a xlink:href=\"https:\/\/github.com\/masak\/workshop\/blob\/master\/$1\.md\">$1<\/a><\/tspan>/ ; print' workshop-map.svg
Update README.md

Added an offsite hosted SVG map with links.
Merge pull request #3 from grtodd/master

Adds links to the SVG map and replaces the PNG version in the README.md