Use boost::noncopyable to avoid copying classes.

git-svn-id: http://svn.gna.org/svn/wesnoth/trunk@56333 75b3775d-3801-0410-9e12-e2e43121521d
Remove the unused function thread::kill().

The underlaying function SDL_KillThread will not be supported by SDL 2.0
so remove the unused function.

git-svn-id: http://svn.gna.org/svn/wesnoth/trunk@56334 75b3775d-3801-0410-9e12-e2e43121521d
Add SDL 2.0 compatibility.

Threads can have a name in SDL 2.0, initialise it with an empty
C-string. Once/if we move to SDL 2.0 we can look whether we want to put
useful information in the string.

git-svn-id: http://svn.gna.org/svn/wesnoth/trunk@56335 75b3775d-3801-0410-9e12-e2e43121521d
Add SDL 2.0 compatibility.

The SDL_PixelFormat in 2.0 misses a few fields so don't use them in the
check in set_pixel_format. (Also added a remark about some not tested
fields in the struct.)

git-svn-id: http://svn.gna.org/svn/wesnoth/trunk@56336 75b3775d-3801-0410-9e12-e2e43121521d
Add SDL 2.0 compatibility.

Switched to using the SDL clipboard routines instead of our own ones.
The disadvantage is that the SDL clipboard has no proper support for the
various X11 clipboards (yet).

git-svn-id: http://svn.gna.org/svn/wesnoth/trunk@56337 75b3775d-3801-0410-9e12-e2e43121521d
Add SDL 2.0 compatibility.

Disable a run-time check required in SDL 1.2 due to a change in glibc.
Later versions of SDL 1.2 already have a fix for this change so no need
to do this for version 2.0.

git-svn-id: http://svn.gna.org/svn/wesnoth/trunk@56338 75b3775d-3801-0410-9e12-e2e43121521d