Increase  INST_INDEX_BITS to 13 avoiding overflow

When shader caching is enabled, the code needs to convert from glsl
to mesa ir to get some information it needs.  In doing so, the shaders
in Heaven and Valley have an index of 4096 that exceeds the
1 <<  INST_INDEX_BITS current maximum.  Freedesktop issue 29418 is
an example of arbitrarily increasing the size to accomodate shader
overflow.
Bump version for LunarG 1.3