(cherry picked from commit ea98a4e0)
Signed-off-by: Steffen Müthing <muething@dune-project.org>

This patch adds the cmake findpackage script which locates Tim Davis' SuiteSparsae collection.

If a certain setting of the SuiteSparse library should be used it can be found using
find_package( SuiteSparse COMPONENETS <list-of-components> )
with a specific list of components.
Existence of components can be check using the SUITESPARSE_<comp>_FOUND/HAVE_SUITESPARSE_<comp> cmake variable.

The UMFPack search routines are redirected to the more general FindSuiteSparse script.

(cherry picked from commit 2f846882)
Signed-off-by: Steffen Müthing <muething@dune-project.org>

Until now, the global properties that hold the collection of flags
for all packages have been updated manually in each find module. It
might be convenient for developers to put this into a macro that
uses CMakeParseArguments.

For generating the config.h file we use the HAVE_* variables instead
of the CMake ones *_FOUND, Unfortunately, we sometines to not set
HAVE_* to the value of the *_FOUND vriable but to its name. Usually
we only query whether these variable are set at all. While
this often (except for psurface) does not pose a problem, it is semantically
wrong. Therfore this patch fixes this.

Kudos to Ansgar for pointing to this problem.

The removed lines would be necessary if the included headers
or libraries would be tested. As this is not the case, they can
be safely removed.
The way they were used, every test tried to link to the libraries
amd and umfpack causing every test to fail if the libraries are
not present. The changed declaration of CMAKE_REQUIRED_* should
be encapsulated together with the test inside
  include(CMakePushCheckState)
  cmake_push_check_state()
and
  cmake_pop_check_state()
to ensure that the definitions do not leak the test.

This patch adds test for both CMake and autotools as the
build system.
UMFPack is used by several dune modules (e.g. fem and istl)
the only common required module by both is common. Therefore
we add the test here to make it usable for all modules.

BTW: These tests are taken from Dominics branch of dune-istl.
     Therefore he deserves the credit for them.