NEW : add an explorer for REST API consultation & documentation

htdocs/public/api/explorer/css/screen.css

htdocs/public/api/explorer/images/pet_store_api.png

htdocs/public/api/explorer/images/throbber.gif

htdocs/public/api/explorer/index.html

htdocs/public/api/explorer/lib/backbone-min.js

htdocs/public/api/explorer/lib/handlebars-1.0.rc.1.js

...ublic/api/explorer/lib/handlebars.runtime-1.0.0.beta.6.js

htdocs/public/api/explorer/lib/jquery-1.8.0.min.js

htdocs/public/api/explorer/lib/jquery.ba-bbq.min.js

htdocs/public/api/explorer/lib/jquery.slideto.min.js

htdocs/public/api/explorer/lib/jquery.wiggle.min.js

htdocs/public/api/explorer/lib/swagger.js

htdocs/public/api/explorer/lib/underscore-min.js

htdocs/public/api/explorer/swagger-ui.js

htdocs/public/api/explorer/swagger-ui.min.js