Potential new style

Wife suggested empty/filled circles like a linear LED display. I think this reads nicely, and hopefully, once I figure out color roles, will be even stronger of a quick visual indicator.

source/arguments_edit/build-overviews.rst

@@ -9,11 +9,11 @@
 ========        ========
 Resource        Impact
 ========        ========
-CPU             ░▓░ | Medium
+CPU             ●●○ | Medium
-GPU             ░░░ | None
+GPU             ○○○ | None
-HDD             ░▓░ | Medium
+HDD             ●●○ | Medium
-RAM             ░▓░ | Medium
+RAM             ●●○ | Medium
-Time            ░▓░ | Medium
+Time            ●●○ | Medium
 ========        ========
 
 ----