* Added instancing support to Vulkan, drawInstanced() test image is upside-down

* Fixed inverted drawInstanced() test output by changing Vulkan viewport convention

* Replaced vkCmdDraw with vkCmdDrawIndexed in all non-indirect indexed draws, drawIndexedIndirect test now working for Vulkan

* Moved index and vertex buffer binding into setIndexBuffer and setVertexBuffers; Defaulted countBuffer to nullptr and countOffset to 0 and added a check for non-null countBuffer to drawIndirect and drawIndexedIndirect in Vulkan; All Vulkan draw tests working (but D3D12 tests broken)

* Added support for drawInstanced and drawIndexedInstanced to D3D11 and added tests for both, however D3D11 tests are currently disabled due to readTextureResource assuming a fixed pixel size (among other possible problems); Fixed issues causing D3D12 tests to fail after major back-end fixes to get Vulkan up and running

* Removed testing function for dumping images and some other commented out code

* Removed some commented out code

* Fix initializer list causing builds to fail (attempt 1)

* Removed initializer list for VertexStreamDesc in createInputLayout() and fill in struct fields normally (build fix attempt 2)

* Removed default values from VertexStreamDesc and changed all initializer lists to reflect this change

* Moved applyBinding before setVertexBuffer in RenderTestApp::renderFrame() to ensure the pipeline has already been bound before vertex buffers are

* Changed D3D11's readTextureResource to calculate pixel size using format-specific size information; Removed wrapper around D3D11 instanced and indexed instanced draw tests