Implemented the Create subcommand (#5)

This PR contains the work done to add the *Build* subcommand that build a *Hummingbird* project from the command line to the `Colibri` command.

Reviewed-on: #5
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Library/Sources/Public/Protocols/Locationable.swift

@@ -0,0 +1,21 @@
+import Foundation
+
+public protocol Locationable {
+    
+    // MARK: Properties
+    
+    var location: String? { get set }
+    
+}
+
+// MARK: - Locationable+Properties
+
+public extension Locationable {
+    
+    // MARK: Properties
+    
+    var locationURL: URL? {
+        location.flatMap { URL(fileURLWithPath: $0) }
+    }
+    
+}

Library/Sources/Public/Tasks/BuildProjectTask.swift

@@ -0,0 +1,29 @@
+import Foundation
+
+public struct BuildProjectTask {
+    
+    // MARK: Properties
+    
+    private let terminalService: TerminalServicing
+    
+    // MARK: Initialisers
+    
+    public init(terminalService: TerminalServicing) {
+        self.terminalService = terminalService
+    }
+    
+    // MARK: Functions
+    
+    public func callAsFunction(at location: URL? = nil) async throws (TerminalServiceError) {
+        let executableURL = URL(at: "/usr/bin/swift")
+
+        var arguments: [String] = ["build"]
+        
+        if let location {
+            arguments.append(contentsOf: ["--package-path", location.pathString])
+        }
+        
+        try await terminalService.run(executableURL, arguments: arguments)
+    }
+    
+}