[WIP] Linux/Android native deploy (#980)

Makefile

apps/android_deploy/.gitignore

apps/android_deploy/README.md

apps/android_deploy/app/.gitignore

apps/android_deploy/app/build.gradle

apps/android_deploy/app/download-models.gradle

apps/android_deploy/app/src/main/AndroidManifest.xml

.../src/main/java/ml/dmlc/tvm/android/demo/MainActivity.java

apps/android_deploy/app/src/main/jni/Android.mk

apps/android_deploy/app/src/main/jni/Application.mk

apps/android_deploy/app/src/main/jni/build.sh

apps/android_deploy/app/src/main/jni/make/config.mk

apps/android_deploy/app/src/main/jni/tvm_runtime.h

.../android_deploy/app/src/main/res/layout/activity_main.xml

apps/android_deploy/app/src/main/res/layout/content_main.xml

apps/android_deploy/app/src/main/res/values/colors.xml

apps/android_deploy/app/src/main/res/values/strings.xml

apps/android_deploy/app/src/main/res/values/styles.xml

apps/android_deploy/app/src/main/res/xml/provider_paths.xml

apps/android_deploy/build.gradle