Merging in changes trunk updates: adding standard error_info typedefs, updating the documentation.

[SVN r55094]

example/Jamfile

@@ -13,3 +13,4 @@ obj cloning_2 : cloning_2.cpp : <threading>multi ;
 obj info_tuple : info_tuple.cpp ;
 obj enable_error_info : enable_error_info.cpp ;
 obj logging : logging.cpp ;
+obj errinfos : errinfos.cpp ;