Allow definition of settings in campaign's yaml file

Resolves #92

resources/campaigns/AssaultonDamascus.yaml

@@ -10,12 +10,13 @@ description: "<p>Edited by HolyOrangeJuice. Original Golan Heights by Khopa. Mod
 miz: AssaultonDamascus.miz
 performance: 2
 version: "10.6"
-max_frontline_length: 30
 recommended_player_money: 2000
 recommended_enemy_money: 2000
 recommended_player_income_multiplier: 1.0
 recommended_enemy_income_multiplier: 1.0
 advanced_iads: false
+settings:
+  max_frontline_length: 30
 squadrons:
   CVN-74 John Stennis:
     - primary: BARCAP

resources/campaigns/Battle4Georgia.yaml

@@ -14,8 +14,6 @@ description: "<p>This mission was designed for the We Run Liberation group [WRL]
   from its Russian neighbours before it's too late!
   </p>"
 miz: Battle4Georgia.miz
-max_frontline_length: 30
-culling_exclusion_radius: 35
 performance: 2
 version: "10.5"
 recommended_player_money: 2000
@@ -23,6 +21,9 @@ recommended_enemy_money: 2000
 recommended_player_income_multiplier: 1.0
 recommended_enemy_income_multiplier: 1.0
 advanced_iads: false
+settings:
+  max_frontline_length: 30
+  perf_culling_distance: 35
 squadrons:
   Blue CV-1:
     - primary: BARCAP

resources/campaigns/Kutaisi2Vaziani.yaml

@@ -8,13 +8,14 @@ recommended_start_date: 2021-10-22
 description: "<p>This mission was designed for the We Run Liberation group [WRL].
   <a style=\"color: white\" href=\"https://werunliberation.com\">werunliberation.com</a></p>"
 miz: Kutaisi2Vaziani.miz
-max_frontline_length: 30
 performance: 2
 version: "10.5"
 recommended_player_money: 2000
 recommended_enemy_money: 2000
 recommended_player_income_multiplier: 3.0
 recommended_enemy_income_multiplier: 1.5
+settings:
+  max_frontline_length: 30
 advanced_iads: true # Campaign has connection_nodes / power_sources / command_centers
 iads_config:
 #REDFOR BASE DEFENSE

resources/campaigns/WRL_PG_Wargames.yaml

@@ -13,7 +13,8 @@ recommended_player_money: 2000
 recommended_enemy_money: 2000
 recommended_player_income_multiplier: 1.5
 recommended_enemy_income_multiplier: 1.5
-max_frontline_length: 30
+settings:
+  max_frontline_length: 30
 squadrons:
   2:
     - primary: AEW&C

resources/campaigns/WRL_up_the_coast.yaml

@@ -21,13 +21,14 @@ description:   "<p>This mission was designed for the We Run Liberation group [WR
   be deployed at once. Each airbase has one or more factories. Each airbase has only three ammo targets. Do not
   destroy these if you wish to use them after you capture them</p>"
 miz: WRL_up_the_coast.miz
-max_frontline_length: 30
 performance: 2
 version: "10.5"
 recommended_player_money: 2000
 recommended_enemy_money: 2000
 recommended_player_income_multiplier: 1.0
 recommended_enemy_income_multiplier: 1.0
+settings:
+  max_frontline_length: 30
 advanced_iads: false
 squadrons:
   Blue CV-1:

resources/campaigns/battle4area51.yaml

@@ -11,14 +11,14 @@ description: "<p>This mission was designed for the We Run Liberation group [WRL]
   <p>The enemy has an Advanced IADs network designed to work with the skynet plugin.</p>
   <p>Look for weakness in enemy SAM defense and go after the command center and power stations.</p>"
 miz: battle4area51.miz
-max_frontline_length: 20
 performance: 1
 version: "10.5"
 recommended_player_money: 2000
 recommended_enemy_money: 2000
 recommended_player_income_multiplier: 1.0
 recommended_enemy_income_multiplier: 1.0
-max_frontline_length: 20
+settings:
+  max_frontline_length: 20
 advanced_iads: true # Campaign has connection_nodes / power_sources / command_centers
 iads_config:
 #COMMAND