fixed ActAs documentation for schema.yml; documented "link_function" option to tag_cloud()
fixed ActAs documentation for schema.yml; documented "link_function" option to tag_cloud()

git-svn-id: 14431f16c86e063b591b7186ad64c5043b5760e0@29511 ee427ae8-e902-0410-961c-c3ed070cd9f9

Symfony-Plugins/sfDoctrineActAsTaggablePlugin,Symfony-Plugins/sfDoctrineActAsTaggablePlugin