Enable MemberImportVisibility check on all targets (#486)

Enable MemberImportVisibility check on all targets. Use a standard
string header and footer to bracket the new block for ease of updating
in the future with scripts.

Package.swift

@@ -90,3 +90,14 @@ let package = Package(
         ),
     ]
 )
+
+// ---    STANDARD CROSS-REPO SETTINGS DO NOT EDIT   --- //
+for target in package.targets {
+    if target.type != .plugin {
+        var settings = target.swiftSettings ?? []
+        // https://github.com/swiftlang/swift-evolution/blob/main/proposals/0444-member-import-visibility.md
+        settings.append(.enableUpcomingFeature("MemberImportVisibility"))
+        target.swiftSettings = settings
+    }
+}
+// --- END: STANDARD CROSS-REPO SETTINGS DO NOT EDIT --- //

Sources/NIOHTTP2/ConnectionStateMachine/HasLocalSettings.swift

@@ -12,6 +12,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+import NIOHPACK
+
 /// A protocol implemented by HTTP/2 connection state machine states with local settings.
 ///
 /// This protocol provides implementations that can apply changes to the local settings.

Sources/NIOHTTP2/ConnectionStateMachine/HasRemoteSettings.swift

@@ -12,6 +12,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+import NIOHPACK
+
 /// A protocol implemented by HTTP/2 connection state machine states with remote settings.
 ///
 /// This protocol provides implementations that can apply changes to the remote settings.

Tests/NIOHTTP2Tests/HTTP2ErrorTests.swift

@@ -12,6 +12,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+import NIOHPACK
 import NIOHTTP2
 import XCTest