Removed svn:ignore for public/plugin_assets directory (#8817).

git-svn-id: http://svn.redmine.org/redmine/trunk@13487 e93f8b46-1217-0410-a6f0-8f06a7374b81
Set svn:ignore to * for plugin_assets subdirectories (#8817).

git-svn-id: http://svn.redmine.org/redmine/trunk@13488 e93f8b46-1217-0410-a6f0-8f06a7374b81