bump rexml (#2078)

Author: joelhawksley

Gemfile.lock

@@ -224,7 +224,7 @@ GEM
     regexp_parser (2.9.2)
     reline (0.5.9)
       io-console (~> 0.5)
-    rexml (3.3.5)
+    rexml (3.3.6)
       strscan
     rspec-core (3.13.0)
       rspec-support (~> 3.13.0)