Fix typos in Writable.swift (#755)

Author: jpsim

Sources/XcodeProj/Protocols/Writable.swift

@@ -1,19 +1,19 @@
 import Foundation
 import PathKit
 
-/// Protocol that defines how an entity can be writed into disk
+/// Protocol that defines how an entity can be written to disk
 public protocol Writable {
     /// Writes the object that conforms the protocol.
     ///
     /// - Parameter path: The path to write to
-    /// - Parameter override: True if the content should be overriden if it already exists.
+    /// - Parameter override: True if the content should be overridden if it already exists.
     /// - Throws: writing error if something goes wrong.
     func write(path: Path, override: Bool) throws
 
     /// Writes the object that conforms the protocol.
     ///
     /// - Parameter pathString: The path string to write to
-    /// - Parameter override: True if the content should be overriden if it already exists.
+    /// - Parameter override: True if the content should be overridden if it already exists.
     /// - Throws: writing error if something goes wrong.
     func write(pathString: String, override: Bool) throws
 }