[MP] Remove SV_[Get|Set]Configstring from the renderer API.  It was only used by an unused function, G2_FindConfigStringSpace.
This commit increases the MP Renderer API version to 5.
[SP] Remove SV_[Get|Set]Configstring from the renderer API.  It was only used by an unused function, G2_FindConfigStringSpace.
This commit increases the SP Renderer API version to 13.