Add settings model (#54)

* Adds a basic settings model

* Added more settings methods; Hooked up initial settings runner to app boot

* Update onboarding flow to use settings model instead of session data

test/pinchflat_web/controllers/page_controller_test.exs

@@ -4,10 +4,12 @@ defmodule PinchflatWeb.PageControllerTest do
   import Pinchflat.ProfilesFixtures
   import Pinchflat.SourcesFixtures
 
+  alias Pinchflat.Settings
+
   describe "GET / when testing onboarding" do
     test "sets the onboarding session to true when onboarding", %{conn: conn} do
-      conn = get(conn, ~p"/")
-      assert get_session(conn, :onboarding)
+      _conn = get(conn, ~p"/")
+      assert Settings.get!(:onboarding)
     end
 
     test "displays the onboarding page when no media profiles exist", %{conn: conn} do
@@ -32,13 +34,13 @@ defmodule PinchflatWeb.PageControllerTest do
 
     test "sets the onboarding session to false when not onboarding", %{conn: conn} do
       conn = get(conn, ~p"/")
-      assert get_session(conn, :onboarding)
+      assert Settings.get!(:onboarding)
 
       _ = media_profile_fixture()
       _ = source_fixture()
 
-      conn = get(conn, ~p"/")
-      refute get_session(conn, :onboarding)
+      _conn = get(conn, ~p"/")
+      refute Settings.get!(:onboarding)
     end
 
     test "displays the home page when not onboarding", %{conn: conn} do