Difficulty info: switch to new lang string extraction

lang/string_extractor/parser.py

@@ -7,6 +7,8 @@
 from .parsers.construction import parse_construction
 from .parsers.construction_category import parse_construction_category
 from .parsers.construction_group import parse_construction_group
+from .parsers.difficulty_impact import parse_difficulty_impact
+from .parsers.difficulty_opt import parse_difficulty_opt
 from .parsers.dream import parse_dream
 from .parsers.effect_on_condition import parse_effect_on_condition
 from .parsers.effect_type import parse_effect_type
@@ -105,8 +107,10 @@ def dummy_parser(json, origin):
     "construction": parse_construction,
     "construction_category": parse_construction_category,
     "construction_group": parse_construction_group,
-    "dream": parse_dream,
+    "difficulty_impact": parse_difficulty_impact,
+    "difficulty_opt": parse_difficulty_opt,
     "disease_type": dummy_parser,
+    "dream": parse_dream,
     "effect_on_condition": parse_effect_on_condition,
     "effect_type": parse_effect_type,
     "emit": dummy_parser,

lang/string_extractor/parsers/difficulty_impact.py

@@ -0,0 +1,5 @@
+from ..write_text import write_text
+
+
+def parse_difficulty_impact(json, origin):
+    write_text(json["name"], origin, comment="Aspect of gameplay affected by difficulty")

lang/string_extractor/parsers/difficulty_opt.py

@@ -0,0 +1,5 @@
+from ..write_text import write_text
+
+
+def parse_difficulty_opt(json, origin):
+    write_text(json["name"], origin, comment="Difficulty rating")