Adjusted and fixed XCB patch.

* Adjusted xcb_icccm calls (for recent XCB versions).
* Fixed wrong parameter order in xcb_icccm_set_wm_protocols call.
* Fixed XCB_BUTTON_RELEASE spawning a MouseButtonPressed event.
* Moved files from obsolete Linux/ to Unix/ directory.
* Added m_useSizeHints fix.
* setTitle() converts to UTF-8 before passing to XCB -> Unicode window title
  support.
* Added XCB-util dependency.
* Replaced XSelectInput. Obtaining XCB connection when taking window handle.
* Adjusted X11 example for XCB.
* Removed AutoPointer, replaced by direct XCB and free() calls.
* Added key repeat workaround.