xrGame: Fixed crashes when loading some saves under Linux

xrRender_R2/r2.cpp: fixed invertion for position decompression params…

… on OpenGL

Update appveyor.yml

Fixed tesselation shaders macros not being defined

Thanks @ShokerStlk for spotting the bug.

m_ShaderOptions was/were forgotten in 31accf9

Removed "alife():object()" duplicate

This partially reverts commit 3f6ee30.

Fixed incorrect paste from clipboard

xrEngine/Environment_render.cpp: use C++11 range-based for

Fixed AppVeyor build cache [skip ci]

Loading screen is now in XML, finally!

Removed dxApplicationRender and cleaned up CApplication
Moved rs_loadingstages from xrRender to xrEngine