GXemul Code2

Release the UI when quitting GXemul::Run.

Separator line, for clarity.

Fixing relative URL to the index page.

Some more minor fixes to make the code build without warning on NetBSD/pmax 5.0 with GNU C++.

Creating a regression test expect script for NetBSD/arc 5.0; updating paths (experiments -> test).

Creating a regression test expect script for NetBSD/arc 5.0; updating paths (experiments -> test).

Moving regression test expect scripts to the test/ directory.

Add an int64_t cast to allow float_emul.cc to build without warnings on NetBSD/pmax 5.0 with GCC.

Updating the NetBSD/pmax regression test expect scripts from 3.1 to 5.0 (for both R3000 and R4400).

Applying another patch from Izumi Tsutsui, for setting the ARCBIOS OSLOADPARTITION environment variable in a more correct way. (Also updating the guest OS page for NetBSD/arc 5.0.)