Log Message:
Changes 0.6.2.1:
* Compilation fixes:
  + sdljoystick.h missing from tarball.
  + Link failure if a widget UI in use and lib765 not available.
  + Compilation failure if ROMSDIR defined.

* Bugfixes:
  + Use of the SDL icons could cause screen corruption.
  + The reverse page mapping for 0xc000 - 0xffff would occasionally be
    wrong on the +2A/+3.

* Miscellaneous:
  + Allow selectable devices to be used for the real joysticks.
  + Use glib 2.0 if available.
  + Allow ROMSDIR to be set when configuring.