Issue/upgrade sundials 510 2

README.md

@@ -14,7 +14,7 @@ Stan Math depends on four libraries:
 
 - Boost (version 1.72.0): [Boost Home Page](https://www.boost.org)
 - Eigen (version 3.3.3): [Eigen Home Page](https://eigen.tuxfamily.org/index.php?title=Main_Page)
-- SUNDIALS (version 4.1.0): [Sundials Home Page](https://computation.llnl.gov/projects/sundials/sundials-software)
+- SUNDIALS (version 5.1.0): [Sundials Home Page](https://computation.llnl.gov/projects/sundials/sundials-software)
 - Intel TBB (version 2019_U8): [Intel TBB Home Page](https://www.threadingbuildingblocks.org)
 
 These are distributed under the `lib/` subdirectory. Only these versions of the dependent libraries have been tested with Stan Math.
@@ -67,7 +67,7 @@ Note that the paths should *not* include the final directories `stan`, `Eigen`,
 ```
 The `math-libs` target has to be called only once, and can be omitted for subsequent compilations.
 
-The standalone makefile ensures that all the required `-I` include statements are given to the compiler and the necessary libraries are linked: `~/stan-dev/math/stan` and `~/stan-dev/math/lib/eigen_3.3.3/Eigen` and `~/stan-dev/math/lib/boost_1.69.0/boost` and `~/stan-dev/math/lib/sundials_4.1.0/include` and `~/stan-dev/math/lib/tbb_2019_U8/include`. The `~/stan-dev/math/lib/tbb` directory is created by the `math-libs` makefile target automatically. The flags `-Wl,-rpath,...` instruct the linker to hard-code the path to the Intel TBB library inside the stan-math directory into the final binary. This way the Intel TBB is found when executing the program.
+The standalone makefile ensures that all the required `-I` include statements are given to the compiler and the necessary libraries are linked: `~/stan-dev/math/stan` and `~/stan-dev/math/lib/eigen_3.3.3/Eigen` and `~/stan-dev/math/lib/boost_1.69.0/boost` and `~/stan-dev/math/lib/sundials_5.1.0/include` and `~/stan-dev/math/lib/tbb_2019_U8/include`. The `~/stan-dev/math/lib/tbb` directory is created by the `math-libs` makefile target automatically. The flags `-Wl,-rpath,...` instruct the linker to hard-code the path to the Intel TBB library inside the stan-math directory into the final binary. This way the Intel TBB is found when executing the program.
 
 Note for Windows users: On Windows the `-rpath` feature as used by Stan Math to hardcode an absolute path to a dynamically loaded library does not work. On Windows the Intel TBB dynamic library `tbb.dll` is located in the `math/lib/tbb` directory. The user can choose to copy this file to the same directory of the executable or to add the directory `path/to/math/lib/tbb` as absolute path to the system-wide `PATH` variable.