Split the Travis checks into two test calls (#2797)

The cppcheck can run for quite a long time, sometimes even more than
10 minutes. This change splits the test execution into two part:
* First, do all checks excluding the cppcheck call with the default timeout.
* Second, do the cppcheck call with a 30 minutes maximum timeout.

JerryScript-DCO-1.0-Signed-off-by: Peter Gal pgal.u-szeged@partner.samsung.com

Author: galpeter

.travis.yml

@@ -12,9 +12,10 @@ script: tools/run-tests.py $OPTS
 matrix:
   include:
     - name: "Checks"
-      env:
-        - OPTS="--check-signed-off=travis --check-cppcheck --check-doxygen --check-vera --check-license --check-magic-strings --check-pylint"
       install: pip install --user pylint==1.6.5
+      script:
+        - tools/run-tests.py --check-signed-off=travis --check-doxygen --check-vera --check-license --check-magic-strings --check-pylint
+        - travis_wait 30 tools/run-tests.py --check-cppcheck
       addons:
         apt:
           packages: [doxygen, cppcheck, vera++]