Redmine

There's a topic on the forum here where the person asks how to revert plugin migrations easily. I think it would be useful if people want to try plugins and then uninstall it.

Engines seems to be able to do that but I didn't managed to make it work. Anyway, I think it's the same as the task to migrate all plugins : Engines know how to do this but a redmine specific task has been added. So I suggest to add a redmine specific task to migrate just one plugin.

I leave a patch in attachment, which is nearly a copy/paste from Engines db:migrate:plugin task.

Usage:
$ rake db:migrate_plugin NAME=my_plugin : migrate to last version of "my_plugin"
$ rake db:migrate_plugin NAME=my_plugin VERSION=X : migrate to version X (and 0 when you uninstall)

Any opinion about that ?