Migrate to Swift 5.

Author: jeantimex

ios-swift-collapsible-table-section.xcodeproj/project.pbxproj

@@ -105,13 +105,13 @@
 				TargetAttributes = {
 					0A908DEA1CFCAA9200470F33 = {
 						CreatedOnToolsVersion = 7.3.1;
-						LastSwiftMigration = 1010;
+						LastSwiftMigration = 1030;
 					};
 				};
 			};
 			buildConfigurationList = 0A908DE61CFCAA9200470F33 /* Build configuration list for PBXProject "ios-swift-collapsible-table-section" */;
 			compatibilityVersion = "Xcode 3.2";
-			developmentRegion = English;
+			developmentRegion = en;
 			hasScannedForEncodings = 0;
 			knownRegions = (
 				en,
@@ -286,8 +286,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "su.ios-swift-collapsible-table-section";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_SWIFT3_OBJC_INFERENCE = On;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Debug;
 		};
@@ -300,8 +299,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = "su.ios-swift-collapsible-table-section";
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_SWIFT3_OBJC_INFERENCE = On;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Release;
 		};