Added Sascha Willems FindXCB.cmake module for finding the XCB library

and headers

neo/cmake/FindXCB.cmake

@@ -0,0 +1,51 @@
+# - FindXCB
+#
+# Copyright 2015 Valve Coporation
+
+find_package(PkgConfig)
+
+if(NOT XCB_FIND_COMPONENTS)
+    set(XCB_FIND_COMPONENTS xcb)
+endif()
+
+include(FindPackageHandleStandardArgs)
+set(XCB_FOUND true)
+set(XCB_INCLUDE_DIRS "")
+set(XCB_LIBRARIES "")
+foreach(comp ${XCB_FIND_COMPONENTS})
+    # component name
+    string(TOUPPER ${comp} compname)
+    string(REPLACE "-" "_" compname ${compname})
+    # header name
+    string(REPLACE "xcb-" "" headername xcb/${comp}.h)
+    # library name
+    set(libname ${comp})
+
+    pkg_check_modules(PC_${comp} QUIET ${comp})
+
+    find_path(${compname}_INCLUDE_DIR NAMES ${headername}
+        HINTS
+        ${PC_${comp}_INCLUDEDIR}
+        ${PC_${comp}_INCLUDE_DIRS}
+        )
+
+    find_library(${compname}_LIBRARY NAMES ${libname}
+        HINTS
+        ${PC_${comp}_LIBDIR}
+        ${PC_${comp}_LIBRARY_DIRS}
+        )
+
+    find_package_handle_standard_args(${comp}
+        FOUND_VAR ${comp}_FOUND
+        REQUIRED_VARS ${compname}_INCLUDE_DIR ${compname}_LIBRARY)
+    mark_as_advanced(${compname}_INCLUDE_DIR ${compname}_LIBRARY)
+
+    list(APPEND XCB_INCLUDE_DIRS ${${compname}_INCLUDE_DIR})
+    list(APPEND XCB_LIBRARIES ${${compname}_LIBRARY})
+
+    if(NOT ${comp}_FOUND)
+        set(XCB_FOUND false)
+    endif()
+endforeach()
+
+list(REMOVE_DUPLICATES XCB_INCLUDE_DIRS)