Teach scss-lint that selectors each get their own line

In our scss, each selector should be on its own line for readability.
scss-lint should complain about scss that has more than one selector on
a line, e.g.:

  .selector-a, .selector-b {

Related Story:
  http://www.pivotaltracker.com/story/show/42151789 (delivered)
  ("Teach scss-lint that selectors each get their own line")

Change-Id: If63df25bd5c275c104eefb4c23ba00d56b403c98
Reviewed-on: https://gerrit.causes.com/17213
Reviewed-by: Aiden Scandella <aiden@causes.com>
Tested-by: Joe Lencioni <joe.lencioni@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Bump version to 0.3

Related Story:
  http://www.pivotaltracker.com/story/show/42151789
  ("Teach scss-lint that selectors each get their own line")

Change-Id: If44fc4a9dea5c48c7e939057f2acb62ee0ebe1ec
Reviewed-on: https://gerrit.causes.com/17214
Tested-by: Joe Lencioni <joe.lencioni@causes.com>
Reviewed-by: Aiden Scandella <aiden@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>