.travis.yml: build our own version of swig
.travis.yml: build our own version of swig

Signed-off-by: Brendan Le Foll <3e0e8c4069934e8b47d99704927a85c66c0ceb33@intel.com>

jontrulson/mraa,stefan-andritoiu/mraa,andreivasiliu2211/mraa,ProfFan/mraa,arfoll/mraa,g-vidal/mraa,arfoll/mraa,ncrastanaren/mraa,Propanu/mraa,Propanu/mraa,intel-iot-devkit/mraa,petreeftime/mraa,alext-mkrs/mraa,Jon-ICS/mraa,Jon-ICS/mraa,intel-iot-devkit/mraa,sergev/mraa,yongli3/mraa,stefan-andritoiu/mraa,alext-mkrs/mraa,stefan-andritoiu/mraa-gpio-chardev,arunlee77/mraa,sergev/mraa,KurtE/mraa,Hbrinj/mraa,malikabhi05/mraa,Jon-ICS/mraa,g-vidal/mraa,w4ilun/mraa,KurtE/mraa,whbruce/mraa,ncrastanaren/mraa,ProfFan/mraa,whbruce/mraa,stefan-andritoiu/mraa,intel-iot-devkit/mraa,spitfire88/mraa,stefan-andritoiu/mraa-gpio-chardev,arfoll/mraa,arunlee77/mraa,petreeftime/mraa,petreeftime/mraa,stefan-andritoiu/mraa-gpio-chardev,malikabhi05/mraa,yongli3/mraa,Propanu/mraa,Propanu/mraa,sergev/mraa,ncrastanaren/mraa,arfoll/mraa,stefan-andritoiu/mraa,yongli3/mraa,ProfFan/mraa,spitfire88/mraa,KurtE/mraa,yongli3/mraa,malikabhi05/mraa,stefan-andritoiu/mraa,ncrastanaren/mraa,w4ilun/mraa,arunlee77/mraa,spitfire88/mraa,alext-mkrs/mraa,malikabhi05/mraa,spitfire88/mraa,Hbrinj/mraa,whbruce/mraa,Hbrinj/mraa,Hbrinj/mraa,yongli3/mraa,andreivasiliu2211/mraa,sergev/mraa,g-vidal/mraa,g-vidal/mraa,arfoll/mraa,g-vidal/mraa,alext-mkrs/mraa,malikabhi05/mraa,stefan-andritoiu/mraa-gpio-chardev,stefan-andritoiu/mraa-gpio-chardev,jontrulson/mraa,jontrulson/mraa,Propanu/mraa,ncrastanaren/mraa,alext-mkrs/mraa,jontrulson/mraa,petreeftime/mraa,sergev/mraa,KurtE/mraa,w4ilun/mraa,whbruce/mraa,arunlee77/mraa,intel-iot-devkit/mraa,ProfFan/mraa,andreivasiliu2211/mraa,jontrulson/mraa,intel-iot-devkit/mraa,andreivasiliu2211/mraa,w4ilun/mraa,KurtE/mraa