docs($q): fix a few typos

Author: vin

src/ng/q.js

@@ -102,7 +102,7 @@
  *     return result + 1;
  *   });
  *
- *   // promiseB will be resolved immediately after promiseA is resolved and it's value will be
+ *   // promiseB will be resolved immediately after promiseA is resolved and its value will be
  *   // the result of promiseA incremented by 1
  * </pre>
  *
@@ -127,7 +127,7 @@
  *  # Testing
  * 
  *  <pre>
- *    it('should simulate promise', inject(function($q, $rootSCope) {
+ *    it('should simulate promise', inject(function($q, $rootScope) {
  *      var deferred = $q.defer();
  *      var promise = deferred.promise;
  *      var resolvedValue;
@@ -312,7 +312,7 @@ function qFactory(nextTick, exceptionHandler) {
    * @methodOf ng.$q
    * @description
    * Wraps an object that might be a value or a (3rd party) then-able promise into a $q promise.
-   * This is useful when you are dealing with on object that might or might not be a promise, or if
+   * This is useful when you are dealing with an object that might or might not be a promise, or if
    * the promise comes from a source that can't be trusted.
    *
    * @param {*} value Value or a promise