Generate generic input layout from correct VS bytecode
Fix highlighting VS output verts with index buffers
Allow fully flexible display of position&other component on meshes

* You can choose which component will be used as 'position' when rendering
  vertex inputs. Helpful if a position component isn't auto-detected, or
  if you want to render UV co-ordinates onto the screen.
* Instead of fixed TEXCOORD0/Color options for solid shading onto the mesh
  you can choose a secondary column yourself.
* Also the solid shading options are available on vertex output meshes as
  well as inputs.