Define property EXCLUDE_FROM_DEFAULT_BUILD

Add definition and documentation of properties EXLCUDE_FROM_DEFAULT_BUILD
and EXCLUDE_FROM_DEFAULT_BUILD_<CONFIG>.

Source/cmTarget.cxx

@@ -265,6 +265,21 @@ void cmTarget::DefineProperties(cmake *cm)
      "whatever file extension is required by the host app for your "
      "bundle.");
 
+  cm->DefineProperty
+    ("EXCLUDE_FROM_DEFAULT_BUILD", cmProperty::TARGET,
+     "Exclude target from \"Build Solution\".",
+     "This property is only used by Visual Studio generators 7 and above. "
+     "When set to TRUE, the target will not be built when you press "
+     "\"Build Solution\".");
+
+  cm->DefineProperty
+    ("EXCLUDE_FROM_DEFAULT_BUILD_<CONFIG>", cmProperty::TARGET,
+     "Per-configuration version of target exclusion from \"Build Solution\". ",
+     "This is the configuration-specific version of "
+     "EXCLUDE_FROM_DEFAULT_BUILD. If the generic EXCLUDE_FROM_DEFAULT_BUILD "
+     "is also set on a target, EXCLUDE_FROM_DEFAULT_BUILD_<CONFIG> takes "
+     "precedence in configurations for which it has a value.");
+
   cm->DefineProperty
     ("FRAMEWORK", cmProperty::TARGET,
      "This target is a framework on the Mac.",