Update contributing to require Apache style license
Update contributing to require Apache style license

Change-Id: Icd3f100bc5bc27231d702122cedeb22ada82598c

Radamanthe/VulkanSamples,Radamanthe/VulkanSamples,Radamanthe/VulkanSamples,Radamanthe/VulkanSamples,Radamanthe/VulkanSamples,Radamanthe/VulkanSamples