Minor edits on PackageDescription source docs.

Author: ElektrojungeAtWork

Sources/PackageDescription4/BuildSettings.swift

@@ -8,7 +8,7 @@
  See http://swift.org/CONTRIBUTORS.txt for Swift project authors
 */
 
-/// The build configuration for a target.
+/// The build configuration such as debug or release..
 public struct BuildConfiguration: Encodable {
     private let config: String
 
@@ -64,7 +64,7 @@ public struct BuildSettingCondition: Encodable {
     ///
     /// - Parameters:
     ///   - platforms: The applicable platforms for this build setting condition.
-    ///   - configuration: The applicable  build configuration for  this build  setting condition.
+    ///   - configuration: The applicable build configuration for this build setting condition.
     public static func when(
         platforms: [Platform]? = nil,
         configuration: BuildConfiguration? = nil
@@ -225,7 +225,7 @@ public struct SwiftSetting: Encodable {
 
     /// Define a compilation condition.
     ///
-    /// Use compilation conditions to only compile a statement if a certain condition is true.
+    /// Use compilation conditions to only compile statements if a certain condition is true.
     /// For example, the Swift compiler will only compile the
     /// statements inside the `#if` block when `ENABLE_SOMETHING` is defined:
     ///     

Sources/PackageDescription4/LanguageStandardSettings.swift

@@ -61,12 +61,6 @@ public enum SwiftVersion {
 
 extension SwiftVersion: Encodable {
 
-    /// Encodes this Swift version into the given encoder.
-    ///
-    /// This function throws an error if any values are invalid for the given encoder’s format.
-    ///
-    /// - Parameters:
-    ///   - encoder: The encoder to write data to.
     public func encode(to encoder: Encoder) throws {
         let value: String
 

Sources/PackageDescription4/Package.swift

@@ -54,9 +54,10 @@ import Foundation
 ///     // swift-tools-version:3.1
 ///     // swift-tools-version:4.0
 ///     // swift-tools-version:5.0
+///     // swift-tools-version:5.1
 ///
 /// The Swift tools version declares the version of the `PackageDescription`
-/// framework, the minimum version of the Swift tools and Swift language
+/// library, the minimum version of the Swift tools and Swift language
 /// compatibility version to process the manifest, and the minimum version of the
 /// Swift tools that are needed to use the Swift package. Each version of Swift
 /// can introduce updates to the `PackageDescription` framework, but the previous
@@ -76,7 +77,7 @@ public final class Package {
       /// Swift package can use. The `Package.resolved` file records the results of the
       /// dependency resolution and lives in the top-level directory of a Swift package.
       /// If you add the Swift package as a package dependency to an app for an Apple platform,
-      /// you can find the `Package.resolved` file inside your `.xcodeproj` or `.xcodeworkspace`.
+      /// you can find the `Package.resolved` file inside your `.xcodeproj` or `.xcworkspace`.
       public class Dependency: Encodable {
 
         /// An enum that represents the requirement for a package dependency.
@@ -163,7 +164,7 @@ public final class Package {
     public var name: String
 
   #if !PACKAGE_DESCRIPTION_4
-    /// The list of platforms that this Swift package supports.
+    /// The list of supported platforms with a custom deployment target.
     @available(_PackageDescription, introduced: 5)
     public var platforms: [SupportedPlatform]? {
         get { return _platforms }
@@ -331,7 +332,7 @@ public final class Package {
     }
 }
 
-/// The system package providers that support Swift packages.
+/// The system package providers used in this Swift package.
 public enum SystemPackageProvider {
 
   #if PACKAGE_DESCRIPTION_4

Sources/PackageDescription4/PackageDependency.swift

@@ -10,7 +10,7 @@
 
 extension Package.Dependency {
 
-    /// Create a package dependency that uses the version rule, starting with the given minimum version,
+    /// Create a package dependency that uses the version requirement, starting with the given minimum version,
     /// going up to the next major version. 
     ///
     /// This is the recommended way to specify a remote package dependency.