Travis CI control file

Signed-off-by: Pekka Enberg <penberg@kernel.org>
Add Travis status to README

Signed-off-by: Pekka Enberg <penberg@kernel.org>
Tweak Travis control file

Signed-off-by: Pekka Enberg <penberg@kernel.org>
Don't redefine CXX

Let people use GCC if they want to.

Signed-off-by: Pekka Enberg <penberg@kernel.org>
Fix JAVA_HOME for Travis CI environment

Signed-off-by: Pekka Enberg <penberg@kernel.org>
Do not redefine $(JAVA_HOME)

Signed-off-by: Jussi Virtanen <jussi.k.virtanen@gmail.com>