Remove description method from SpaceBeforeBrace
Remove description method from SpaceBeforeBrace

The `description` method is being deprecated.

While here, also changed from appending to the `@lints` instance
variable directly to using the `add_lint` helper.

Change-Id: If2902858e2cd29c06759294c4d6357690aec6017
Reviewed-on: http://gerrit.causes.com/36725
Tested-by: jenkins <d95b56ce41a2e1ac4cecdd398defd7414407cc08@causes.com>
Reviewed-by: Shane da Silva <6f6e68d1df92f30cb4b3ce35260ddf94a402f33d@causes.com>

ivantsepp/scss-lint,ingdir/scss-lint,bkeepers/scss-lint,baileyparker/scss-lint,golmansax/scss-lint,davecarter/scss-lint,dwayhs/scss-lint,philipgiuliani/scss-lint,gatero/scss-lint,gajus/scss-lint,teoljungberg/scss-lint,chatzipan/scss-lint,cih/scss-lint,leseulsteve/scss-lint