css: clean up <ul> css.

* Remove `list-style-type: none` rules (this is the default).
* Add `list-bulleted` and `list-inline` utility classes.
* Wrap terms of service and user deletion pages in dtext `.prose` class
  so we don't have to redefine basic list styles on these pages.

app/javascript/src/styles/base/020_base.scss

@@ -101,7 +101,6 @@ menu {
   li {
     margin: 0;
     padding: 0 0.2em;
-    list-style-type: none;
     display: inline;
   }
 }
@@ -123,3 +122,13 @@ table tfoot {
 .fixed-width-container {
   max-width: 70em;
 }
+
+ul.list-bulleted {
+  list-style: inside disc;
+}
+
+ul.list-inline {
+  &, li {
+    display: inline;
+  }
+}