Add htaccess file for routing all requests under api/2 to the new index.php file.  Added index.php catcher file that shows what's being requested.  Added small tweak to io.php which forces JSON if there is a 'format' query string with the value 'json' - useful when testing via browser to enable switching between PHP var_dump and json output.
Moved logic from api into io.php so that v1 and v2 api are now using the same code (because v2 will be similar, except that it shall correctly use HTTP verbs instead of v1's /add vernacular).  For now /api/2/links works
Implemented first part of the V2 API which supports more RESTful use of HTTP verbs to denote actions to be taken.  V1 API still works, but client has been migrated to start to use the new API.