fix: correct spelling of variadic options (#41)

Author: djbe

Sources/ArgumentDescription.swift

@@ -155,7 +155,7 @@ open class Options<T : ArgumentConvertible> : ArgumentDescriptor {
 }
 
 
-open class VaradicOption<T : ArgumentConvertible> : ArgumentDescriptor {
+open class VariadicOption<T : ArgumentConvertible> : ArgumentDescriptor {
   public typealias ValueType = [T]
 
   open let name:String

Tests/CommanderTests/ArgumentParserSpec.swift

@@ -90,15 +90,15 @@ public func testArgumentParser() {
 
     $0.describe("variadic options") {
       $0.it("should return arguments for option") {
-        let option = VaradicOption<String>("varOption")
+        let option = VariadicOption<String>("varOption")
         let values = try option.parse(parser)
         try expect(values.count) == 2
         try expect(values.first) == "varValue1"
         try expect(values.last) == "varValue2"
       }
 
       $0.it("should return empty array when option is unknown") {
-        let option = VaradicOption<String>("unknown")
+        let option = VariadicOption<String>("unknown")
         let values = try option.parse(parser)
         try expect(values.count) == 0
       }