[travis] split up groundtest into two suites

.travis.yml

@@ -36,7 +36,8 @@ env:
     - SUITE=RocketSuiteA
     - SUITE=RocketSuiteB
     - SUITE=RocketSuiteC
-    - SUITE=GroundtestSuite
+    - SUITE=GroundtestSuiteA
+    - SUITE=GroundtestSuiteB
     - SUITE=UnittestSuite
 
 # blacklist private branches