Fix static code analysis warnings in Visual Studio 2019
Fix static code analysis warnings in Visual Studio 2019

Fix the three warnings below. This fixes Issue #88 (noexcept). Not sure if the signed/unsigned char fix is ok for platforms other than Windows.

Utilities\DxFileUtility\DxFileUtility\args.hxx (232, 0)
Utilities\DxFileUtility\DxFileUtility\args.hxx(232,0): Warning C6330: 'char' passed as _Param_(1) when 'unsigned char' is required in call to 'isspace'.
Utilities\DxFileUtility\DxFileUtility\args.hxx (466, 0)
Utilities\DxFileUtility\DxFileUtility\args.hxx(466,0): Warning C26439: This kind of function may not throw. Declare it 'noexcept' (f.6).
Utilities\DxFileUtility\DxFileUtility\args.hxx (2021, 0)
Utilities\DxFileUtility\DxFileUtility\args.hxx(2021,0): Warning C6330: 'char' passed as _Param_(1) when 'unsigned char' is required in call to 'isspace'.
Taywee/args,Taywee/args