Merge branch 'add_finder_andresgraph' into 'master'

Add finder for http://www.andres.sc/graph.html

See merge request !50

cmake/FindANDRESGRAPH.cmake

+# http://www.andres.sc/graph.html
+# We call it andresgraph to avoid ambiguity
+
+# - Try to find ANDRESGRAPH
+# Once done this will define
+#  ANDRESGRAPH_FOUND         - System has ANDRESGRAPH
+#  ANDRESGRAPH_INCLUDE_DIRS  - The ANDRESGRAPH include directories
+
+if (ANDRESGRAPH_INCLUDE_DIR)
+  # in cache already
+  set(ANDRESGRAPH_FOUND TRUE)
+  set(ANDRESGRAPH_INCLUDE_DIRS "${ANDRESGRAPH_INCLUDE_DIR}" )
+else (ANDRESGRAPH_INCLUDE_DIR)
+
+find_path( ANDRESGRAPH_INCLUDE_DIR 
+	   NAMES andres/graph/multicut-lifted/kernighan-lin.hxx
+           PATHS $ENV{ANDRESGRAPH_DIR}
+                 /usr/include/
+                 /usr/local/include/
+                 /opt/local/include/
+          )
+
+set(ANDRESGRAPH_INCLUDE_DIRS "${ANDRESGRAPH_INCLUDE_DIR}" )
+
+
+include(FindPackageHandleStandardArgs)
+# handle the QUIETLY and REQUIRED arguments and set LIBCPLEX_FOUND to TRUE
+# if all listed variables are TRUE
+find_package_handle_standard_args(ANDRESGRAPH  DEFAULT_MSG
+                                  ANDRESGRAPH_INCLUDE_DIR)
+
+mark_as_advanced(ANDRESGRAPH_INCLUDE_DIR)
+
+endif(ANDRESGRAPH_INCLUDE_DIR)