CMake WIP

Not working:
 - option(... check)
 - not finished everything (see XXX and FIXME)
 - still halway converting

cmake/Version.cmake

+# Converts a version such as 1.2.255 to 0x0102ff
+function(HexVersion version_hex_var major minor patch)
+  math(EXPR version_dec "${major} * 256 * 256 + ${minor} * 256 + ${patch}")
+  set(version_hex "0x")
+  foreach(i RANGE 5 0 -1)
+    math(EXPR num "(${version_dec} >> (4 * ${i})) & 15")
+    string(SUBSTRING "0123456789abcdef" ${num} 1 num_hex)
+    set(version_hex "${version_hex}${num_hex}")
+  endforeach()
+  set(${version_hex_var} "${version_hex}" PARENT_SCOPE)
+endfunction()

cmakeconfig.h.in

+
+/* Define to 1 if you have the `std::map::emplace`. */
+#cmakedefine HAVE_STD_MAP_EMPLACE 1
+
+/* Define to 1 if you have `libjansson` library. */
+#cmakedefine HAVE_JANSSON 1
+
+/* Define to 1 if you have `libxml2` library. */
+#cmakedefine HAVE_LIBXML2 1
+
+/* Define to 1 if you have `spdylay` library. */
+#cmakedefine HAVE_SPDYLAY 1