make the build system compatible with Dune's cmake build system

before this, dune modules that are not using the OPM build system
needed to treat opm-parser as an external library. With this patch,
opm-parser can be build as part of duncontrol build chains, i.e.,
other modules just need to specify a depencency on opm-parser in their
dune.module file and opm-parser's libraries and headers get picked up
just fine.

Things like generating opm-parser-config.cmake should quite likely be
done in a better way, but I'm not really a cmake expert and the
solution proposed in this patch seems to get things done regardless of
whether opm-parser is system-installed or not. Comprehensive solutions
are highly appreciated.

config.h.cmake

@@ -0,0 +1,50 @@
+/* begin opm-parser
+   put the definitions for config.h specific to
+   your project here. Everything above will be
+   overwritten
+*/
+/* begin private */
+/* Name of package */
+#define PACKAGE "@DUNE_MOD_NAME@"
+
+/* Define to the address where bug reports for this package should be sent. */
+#define PACKAGE_BUGREPORT "@DUNE_MAINTAINER@"
+
+/* Define to the full name of this package. */
+#define PACKAGE_NAME "@DUNE_MOD_NAME@"
+
+/* Define to the full name and version of this package. */
+#define PACKAGE_STRING "@DUNE_MOD_NAME@ @DUNE_MOD_VERSION@"
+
+/* Define to the one symbol short name of this package. */
+#define PACKAGE_TARNAME "@DUNE_MOD_NAME@"
+
+/* Define to the home page for this package. */
+#define PACKAGE_URL "@DUNE_MOD_URL@"
+
+/* Define to the version of this package. */
+#define PACKAGE_VERSION "@DUNE_MOD_VERSION@"
+
+/* end private */
+
+/* Define to the version of opm-parser */
+#define OPM_PARSER_VERSION "${OPM_PARSER_VERSION}"
+
+/* Define to the major version of opm-parser */
+#define OPM_PARSER_VERSION_MAJOR ${OPM_PARSER_VERSION_MAJOR}
+
+/* Define to the minor version of opm-parser */
+#define OPM_PARSER_VERSION_MINOR ${OPM_PARSER_VERSION_MINOR}
+
+/* Define to the revision of opm-parser */
+#define OPM_PARSER_VERSION_REVISION ${OPM_PARSER_VERSION_REVISION}
+
+/* Specify whether ERT/libecl is available or not */
+#cmakedefine HAVE_ERT 1
+#cmakedefine HAVE_LIBECL 1
+
+/* begin bottom */
+
+/* end bottom */
+
+/* end opm-parser */

opm-parser-config.cmake.in

@@ -0,0 +1,18 @@
+if(NOT opm-parser_FOUND)
+  #import the target
+  get_filename_component(_dir "${CMAKE_CURRENT_LIST_FILE}" PATH)
+  include("${_dir}/opm-parser-targets.cmake")
+
+  #report other information
+  set(opm-parser_INSTALLED "@OPM_PARSER_INSTALLED@")
+  set(opm-parser_PREFIX "@OPM_PARSER_PREFIX@")
+  set(opm-parser_INCLUDE_DIRS "@OPM_PARSER_INCLUDEDIRS@")
+  set(opm-parser_LIBRARY_DIRS "@OPM_PARSER_LIBDIRS@")
+  set(opm-parser_CXX_FLAGS "@CMAKE_CXX_FLAGS@")
+  set(opm-parser_CXX_FLAGS_DEBUG "@CMAKE_CXX_FLAGS_DEBUG@")
+  set(opm-parser_CXX_FLAGS_MINSIZEREL "@CMAKE_CXX_FLAGS_MINSIZEREL@")
+  set(opm-parser_CXX_FLAGS_RELEASE "@CMAKE_CXX_FLAGS_RELEASE@")
+  set(opm-parser_CXX_FLAGS_RELWITHDEBINFO "@CMAKE_CXX_FLAGS_RELWITHDEBINFO@")
+  set(opm-parser_LIBRARIES "opmparser")
+  set(opm-parser_MODULE_PATH "@OPM_PARSER_MODULE_PATH@")
+endif(NOT opm-parser_FOUND)

opm-parser.pc.in

@@ -0,0 +1,15 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=${prefix}
+libdir=${prefix}/lib
+includedir=${prefix}/include
+CXX=@CMAKE_CXX_COMPILER@
+CC=@CMAKE_C_COMPILER@
+DEPENDENCIES=
+
+Name: opm-parser
+Version: @VERSION@
+Description: The opm-parser module
+URL: http://www.opm-project.org/
+Requires: ${DEPENDENCIES}
+Libs: -L${libdir} -lopmparser
+Cflags: -I${includedir}

src/opm/parser/eclipse/CMakeLists.txt

@@ -152,7 +152,7 @@ endforeach()
 add_static_analysis_tests(opmparser_SRC opmparser_INCLUDES)
 
 install(TARGETS opmparser
-        EXPORT  opm-parser-config
+        EXPORT  opm-parser-targets
         ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
         LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
         RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})