FeatStd Util

Utility to safely access Strings character array 
 Experience showed that users have stored the char* from FeatStd::String::GetCString() resulting in crash when the pointer gets invalid. Therefore a new class FeatStd::CStringAccess has been introduced. Instances of this class can be initialized by FeatStd::String::GetCStringAccess() . The internal char* string is copied (by considering thread safe access). On deletion the memory is overwritten with a pattern before to ease later debugging or core dump analysis.