Fix @typedef name to be dot-separated.

After reviewing other @ typedef definitions in other files, updated this one to use `.` instead of `/` for separators in the name. 

This also fixes a warning in the dash docset generation script, which issues a warning when it encounters an invalid typedef name. 
After reading <http://javascriptmvc.com/docs/DocumentJS.tags.typedef.html>, I am still unsure of what the TYPE section of a typedef means. Also, the links to `TYPE` and `type expression` result in 404.