* enh(Logger): simplified logging macros.
* enh(Delegate): Simplify code with constexpr and std::conditional_t.
* enh(NumericString): Simplify code with constexpr and std::is_signed_v.
* enh(MetaProgramming): Simplify code with C++17 equivalents.
* enh(Tuple): Simplify code with C++17 equivalents.
* enh(TypeList): Remove metaprogramming features that are not used.
* enh(Modules): Remove obsolete Foundation functionality
* enh(Foundation): Compile and run deprecated functionality only when POCO_TEST_DEPRECATED is enabled. Update comments for deprecated functionality.
* fix(Modules): Add missing conditional forward declarations for Foundation.