GRIM: Add a vertex buffer object for blast text drawing

This makes it so that we don't have to destroy the VBO
that a blast text object uses. This fixes what is probably
a driver bug with the windows nvidia drivers.
Merge pull request #821 from klusark/fixcrash

GRIM: Add a vertex buffer object for blast text drawing
ANDROID: Remove INTERNET permission
ANDROID: Make androidrelease use ant release
Merge pull request #823 from klusark/androidbuild

ANDROID: Make androidrelease use ant release
ANDROID: Remove old feature requirements

These don't seem to work as intended as they cause the play store to limit us to 23 devices.
ANDROID: Install to internal by default

Remove android:installLocation="preferExternal" as it is not needed for such a small app.
ANDROID: Update the NDK toolchain to 15
ANDROID: Don't install source files to apk

If ant is let loose on backends/platform/android it copies everything it can into the final apk file, which we obviously don't want. This changes it so that it will only see the java files which it compiles puts the results into the apk.
GRIM: Add a constructor for Shadow

This lets us get rid of the loop in Actor and lets us ensure
that Shadow is initizlied even if constructed elsewhere.
GRAPHICS: Stencil for grim shadows [OpenGLS]
GRAPHICS: Transpose view/model matrices correctly
GRAPHICS: Add shadow mode to grim actors [OpenGLS]
Merge pull request #824 from Botje/grim-shadows

OpenGLS: Support shadows in Grim
ANDROID: Remove proguard files

These are for obfuscation, which we don't need
GRAPHICS: Distinguish between texture size and viewport size in Graphics::FrameBuffer
ANDROID: Remove Unpacker and plugin related things

Also remove the splash screen that happend during unpacking.
GUI: Hide midi and mt-32
ALL: sync with scummvm
Merge pull request #826 from klusark/unpacker

ANDROID: Remove Unpacker and plugin related things