#19 Shell controls: remove the Windows 2000 display name workaround

[Thomas Mueller]

components/c_dzShellControls.pas asks for a folder's display name again with SHGDN_NORMAL when the result starts with ::{, with the TODO "Remove this hack (on Win2k, GUIDs are returned for the PathName of standard folders)". Needs checking whether current Windows versions still need it before removing it.

From the TODO scan in issue 12 of dzlib's ISSUES.md.