[Ipopt] Ipopt maintenance release 3.12.8

[Stefan Vigerske]

Hi,

I just created a new Ipopt maintenance release.
If you were using a recent Ipopt version successfully, then there is no 
need to update.

Here is a list of changes:
- add define for FORTRAN_INTEGER_TYPE to config_ipopt_default.h
- IpoptApplication::RethrowNonIpoptException() now returns whether
   non-ipopt exceptions were rethrown before the method was called.

The source tarballs should be available tomorrow.

Enjoy,
Stefan