exposing some conveniences for manipulating a build phase

Author: g-Off

Sources/XcodeProject/Objects+Extensions/PBXReference+Extensions.swift

@@ -9,6 +9,11 @@
 import Foundation
 
 public extension PBXReference {
+	var parentGroup: PBXGroup? {
+		return  parent as? PBXGroup
+	}
+}
+
 public extension PBXReference {
 	var url: URL? {
 		guard let sourceTree = sourceTree else { return nil }

Sources/XcodeProject/Objects/Build Phases/PBXBuildPhase.swift

@@ -24,11 +24,19 @@ public class PBXBuildPhase: PBXObject {
 	var runOnlyForDeploymentPostprocessing: Bool?
 	var buildActionMask: Int32 = Int32.max
 
-	func remove(file: PBXBuildFile) {
+	public func insert(contentsOf buildFiles: [PBXBuildFile], at index: Int) {
+		files.insert(contentsOf: buildFiles, at: index)
+	}
+	
+	public func remove(file: PBXBuildFile) {
 		guard let index = files.index(of: file) else { return }
 		files.remove(at: index)
 	}
 
+	public func remove(at index: Int) {
+		files.remove(at: index)
+	}
+	
 	override func willMove(from: PBXObject?) {
 		super.willMove(from: from)
 		files.forEach {