Add some South Atlantic naval assets (#23)

- Unit yamls for several ships and added some new ones to uk_1990.json
- 2 new layouts: Aircraft Carrier / LHA with Frigate escorts
- Add "HMS Invincible" as Control Point

resources/layouts/naval/Carrier_Group_Frigates.yaml

@@ -0,0 +1,17 @@
+name: Carrier Group with Frigate escort
+generic: true
+tasks:
+  - AircraftCarrier
+groups:
+  - Carrier:
+    - name: Carrier Group 0
+      unit_count:
+        - 1
+      unit_classes:
+        - AircraftCarrier
+  - Escort:
+    - name: Carrier Group 1
+      unit_count:
+        - 4
+      unit_classes:
+        - Frigate

resources/layouts/naval/LHA_Group_Frigates.yaml

@@ -0,0 +1,17 @@
+name: LHA Group with Frigate escort
+generic: true
+tasks:
+  - HelicopterCarrier
+groups:
+  - LHA:
+    - name: LHA Group 0
+      unit_count:
+        - 1
+      unit_classes:
+        - HelicopterCarrier
+  - Escort:
+    - name: LHA Group 1
+      unit_count:
+        - 2
+      unit_classes:
+        - Frigate