Add Antarctica Map (#544)

## Description:
This PR adds the new Deglaciated Antarctica map(suggested by Backn). It
has 9 nations - most of the country territorial claims on the continent
and the "Penguin Empire".

fixes #545 

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced
- [x] I understand that submitting code with bugs that could have been
caught through manual testing blocks releases and new features for all
contributors

## Please put your Discord username so you can be contacted if a bug or
regression is found:

Nikola123

---------

Co-authored-by: Loymdayddaud <145969603+TheGiraffe3@users.noreply.github.com>

resources/lang/en.json

@@ -122,6 +122,7 @@
     "betweentwoseas": "Between Two Seas",
     "knownworld": "Known World",
     "faroeislands": "Faroe Islands",
+    "deglaciatedantarctica": "Deglaciated Antarctica",
     "europeclassic": "Europe (classic)"
   },
   "map_categories": {

resources/maps/DeglaciatedAntarctica.json

@@ -0,0 +1,61 @@
+{
+  "name": "Deglaciated Antarctica",
+  "width": 2300,
+  "height": 1840,
+  "nations": [
+    {
+      "coordinates": [1545, 785],
+      "name": "Penguin Empire",
+      "strength": 2,
+      "flag": "an_pe"
+    },
+    {
+      "coordinates": [1365, 155],
+      "name": "Norwegian Claim",
+      "strength": 2,
+      "flag": "no"
+    },
+    {
+      "coordinates": [1810, 450],
+      "name": "Upper Australian Claim",
+      "strength": 2,
+      "flag": "au"
+    },
+    {
+      "coordinates": [1980, 980],
+      "name": "Lower Australian Claim",
+      "strength": 1,
+      "flag": "au"
+    },
+    {
+      "coordinates": [495, 605],
+      "name": "Argentinian Claim",
+      "strength": 2,
+      "flag": "ar"
+    },
+    {
+      "coordinates": [1150, 715],
+      "name": "United Kingdom Claim",
+      "strength": 2,
+      "flag": "gb"
+    },
+    {
+      "coordinates": [1060, 935],
+      "name": "Chilean Claim",
+      "strength": 2,
+      "flag": "cl"
+    },
+    {
+      "coordinates": [1365, 1400],
+      "name": "New Zealand Claim",
+      "strength": 2,
+      "flag": "nz"
+    },
+    {
+      "coordinates": [1590, 1120],
+      "name": "French Claim",
+      "strength": 2,
+      "flag": "fr"
+    }
+  ]
+}