mv the mpreal copy in its own folder

unsupported/Eigen/MPRealSupport

@@ -45,6 +45,8 @@ namespace Eigen {
     * via the <a href="http://www.holoborodko.com/pavel/mpfr">MPFR C++</a>
     * library which itself is built upon <a href="http://www.mpfr.org/">MPFR</a>/<a href="http://gmplib.org/">GMP</a>.
     *
+    * You can find a copy of MPFR C++ that is known to be compatible in the unsupported/test/mpreal folder.
+    *
     * Here is an example:
     *
 \code

unsupported/test/CMakeLists.txt

@@ -82,7 +82,7 @@ ei_add_test(FFT)
 find_package(MPFR 2.3.0)
 find_package(GMP)
 if(MPFR_FOUND)
-  include_directories(${MPFR_INCLUDES})
+  include_directories(${MPFR_INCLUDES} ./mpreal)
   ei_add_property(EIGEN_TESTED_BACKENDS "MPFR C++, ")
   set(EIGEN_MPFR_TEST_LIBRARIES ${MPFR_LIBRARIES} ${GMP_LIBRARIES})
   ei_add_test(mpreal_support "" "${EIGEN_MPFR_TEST_LIBRARIES}" )

unsupported/test/mpreal_support.cpp

@@ -42,6 +42,6 @@ void test_mpreal_support()
 }
 
 extern "C" {
-#include "dlmalloc.c"
+#include "mpreal/dlmalloc.c"
 }
-#include "mpreal.cpp"
+#include "mpreal/mpreal.cpp"