Task symfony:set_permissions invokes task deploy:set_permissions:* for each server in "release_roles :all"

Hi,

I'm working against capistrano `3.8` with capistrano-symfony `1.0.0.rc2` and I'm receiving the following error when deploying to an application with more than one host configured:


Due to the nature of Rake each task can only be invoked once (unless manually reset with `Rake::Task[...].reenable`). Task `symfony:set_permissions` on line 61 of `lib/capistrano/tasks/symfony.rake` calls Capistrano DSL method `invoke` inside an `on` block:
```
task :set_permissions do
on release_roles :all do
if fetch(:permission_method) != false
invoke "deploy:set_permissions:#{fetch(:permission_method).to_s}"
end
end
end
```
This means that if there are multiple hosts defined and `release_roles :all` returns more than one then the call to `invoke` happens more than once. Looking at the implementation of task `deploy:set_permissions:acl` for example, we see that it filters the hosts itself anyway:
```
task :acl => [:check] do
...
on roles fetch(:file_permissions_roles) do |host|
...
```
... and therefore applying a filter in `symfony:set_permissions` won't do anything anyway. Proposed fix is to remove the filtering:
```
task :set_permissions do
if fetch(:permission_method) != false
invoke "deploy:set_permissions:#{fetch(:permission_method).to_s}"
end
end
```

Start in lib/capistrano/tasks/symfony.rake around line 61 and inspect how symfony:set_permissions invokes the deploy:set_permissions:* task inside the host iteration. Compare this with deploy:set_permissions:acl and its own host filtering. Done means a multi-host deployment invokes the selected permissions task only once while still applying permissions to the configured roles.

Written by the indexing model from the issue text.