Remove two fixes that were backported to RC

changelog.html

@@ -70,12 +70,6 @@ Upcoming changes</a>
 </div><!--=END=-->
 <h3><a name=v1.602>What's new in 1.602</a> (2015/03/08)</h3>
 <ul class=image>
-  <li class="major bug">
-    Regression with environment variables in 1.600.
-    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-27188">issue 27188</a>)
-  <li class="major bug">
-    Errors with concurrent matrix builds since 1.597.
-    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-26739">issue 26739</a>)
   <li class="rfe">
     Show displayName in build remote API.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-26723">issue 26723</a>)