Update comments and text from midnight -> dark blue

_locales/en/messages.json

@@ -1588,7 +1588,7 @@
 		}
 	},
 	"hub_supporter_perk_themes_description": {
-		"message": "Customize the Ghostery colors - try our Midnight theme!"
+		"message": "Customize the Ghostery colors - try our Dark Blue theme!"
 	},
 	"hub_supporter_perk_stats_description": {
 		"message": "View your blocking statistics and see how Ghostery is working for you"
@@ -1603,7 +1603,7 @@
 		"message": "We strive to deliver the best privacy protection services to our users free of cost. While we do not charge for our privacy suite, you may choose to support us through a small monthly subscription. Join us in our mission by upgrading to Ghostery Plus - and unlock cool perks along the way!"
 	},
 	"hub_supporter_feature_theme_description": {
-		"message": "Customize the Ghostery colors for a new visual experience! Introduced through popular request. Check out our special Midnight theme, and more to come."
+		"message": "Customize the Ghostery colors for a new visual experience! Introduced through popular request. Check out our special Dark Blue theme, and more to come."
 	},
 	"hub_supporter_feature_stats_description": {
 		"message": "View historical blocking results with graphs and statistics to reveal trends and learn how Ghostery has affected your browsing."

app/scss/partials/_stats_graph.scss

@@ -1,5 +1,5 @@
 /* NOTE: will need to use color variables in CSS rather than D3 code accessors
-so that you can support switching between midnight theme and regular theme */
+so that you can support switching between dark blue theme and regular theme */
 
 // Function helper with color variables
 @function _url-friendly-color($color) {