Add missing help (#86)

* Adjust Start-Up section label
* Add help for the allowed services list
* Add help for the zones list

src/lib/y2firewall/widgets/allowed_services.rb

@@ -81,6 +81,17 @@ def handle(event)
         nil
       end
 
+      # @macro seeAbstractWidget
+      def help
+        # TRANSLATORS: %s is the zone label
+        format(
+          _("<p>Select which services you want to allow in the zone <b>%s</b>\n" \
+            "by adding them to the <b>Allowed</b> list (using <b>Add</b> or <b>Add All</b>\n" \
+            "buttons).</p>"),
+          zone.name
+        )
+      end
+
     private
 
       # @!attribute [r] known_svcs_table

src/lib/y2firewall/widgets/pages/startup.rb

@@ -38,7 +38,7 @@ def initialize(_pager)
 
         # @macro seeAbstractWidget
         def label
-          _("Startup")
+          _("Start-Up")
         end
 
         # @macro seeCustomWidget

src/lib/y2firewall/widgets/zones_table.rb

@@ -93,6 +93,22 @@ def selected_zone
         zones.find { |z| z.name == value.to_s }
       end
 
+      # @macro seeAbstractWidget
+      def help
+        _(
+          "<p>A network zone defines the level of trust for network connections.</p>\n" \
+          "<p>You can designate one of them as the <b>default</b> zone by clicking the\n" \
+          "<b>Set As Default</b> button.</p>\n\n" \
+          "<p>In the <b>Interfaces</b> column you see which interfaces are assigned\n" \
+          "to a given zone. Bear in mind that, for the zone which is set as the default\n" \
+          "one, you will see the interfaces that are implicitly assigned to it, i.e.,\n" \
+          "those interfaces that are not assigned explicitly to that zone but to the\n" \
+          "default one.</p>\n\n" \
+          "<p>If you want to assign an interface to a given zone, just visit the\n" \
+          "<b>Interfaces</b> section.</p>"
+        )
+      end
+
     private
 
       # @return [Y2Firewalld::Widgets::DefaultZoneButton] Button to set a zone as 'default'