travis: first executing shorter running scripts

.travis.yml

@@ -43,20 +43,23 @@ script:
     - make -s -C ./examples/default info-concurrency
     - git rebase riot/master || git rebase --abort
 
-    - ./dist/tools/compile_test/compile_test.py
-    - make -C ./tests/unittests test BOARD=native
-    - make -C ./tests/unittests test BOARD=qemu-i386
     - ./dist/tools/licenses/check.sh master
 # TODO:
+#   Remove the `AC` argument when all headers have been
+#   taken care of in master.
+    - ./dist/tools/externc/check.sh master AC
+
+# TODO:
 #   Remove all but `master` parameters to cppcheck (and remove second
 #   invocation) once all warnings of cppcheck have been taken care of
 #   in master.
     - ./dist/tools/cppcheck/check.sh master --diff-filter=MR --error-exitcode=0
     - ./dist/tools/cppcheck/check.sh master --diff-filter=AC
-# TODO:
-#   Remove the `AC` argument when all headers have been
-#   taken care of in master.
-    - ./dist/tools/externc/check.sh master AC
+
+    - make -C ./tests/unittests all test BOARD=native
+    - make -C ./tests/unittests all test BOARD=qemu-i386
+
+    - ./dist/tools/compile_test/compile_test.py
 
 notifications:
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