docs(core/facade/collection): Correct typo

Add correct spelling of the word "statically" Closes angular#4193

Author: machineloop

modules/angular2/src/core/facade/collection.ts

@@ -166,7 +166,7 @@ export class StringMapWrapper {
 export interface Predicate<T> { (value: T, index?: number, array?: T[]): boolean; }
 
 export class ListWrapper {
- // JS has no way to express a staticly fixed size list, but dart does so we
+ // JS has no way to express a statically fixed size list, but dart does so we
  // keep both methods.
  static createFixedSize(size: number): any[] { return new Array(size); }
  static createGrowableSize(size: number): any[] { return new Array(size); }