Port to CHICKEN 5

This release includes changes for compatibility with CHICKEN 5.

SUNDIALS version detection fixes

This release includes a fix so that the setup procedure no longer depends on try-compile placing the compiled file in the current directory.

More robust SUNDIALS version detection procedure

This release includes an update to the SUNDIALS version detection procedure in the setup file, which now allows the version to be set via an environment variable SUNDIALS_VERSION.

Compatibility with argvector CHICKEN

This release includes support changes made to the CHICKEN C API in release 4.10.1.

Updates to event interface

2.12

set version to 2.12 in .setup file