std.exception: Improve ErrnoException based on StdioException
std.stdio: Make StdioException a subclass of ErrnoException
std.process: Replace uses of StdioException
std.stdio: Replace uses of StdioException
std.stdio: Replace StdioException with an alias
std.stdio: Remove unused private binaryWrite function
std.stdio: Update documentation
std.process: Replace ProcessException with OSException
std.file: Update documentation
std.datetime: Update documentation
std.mmfile: Update documentation
std.process: Replace uses of sysErrorString
std.windows.charset: Replace uses of sysErrorString
std.stdio: XREF exceptions in documentation