Add vtlock command for tests to ensure graphics exclusivity
Don't explicitly include core.
Don't override the log fd
Add xephyr and xorg tests.
Tweak test timing; unmount-chroot is still an issue.
Fix xorg/xephyr test command
test/35-xorg: Dump OpenGL+dri information
35/36-xorg/xephyr: Update to new split test
test/run.sh: Change vtlock function

So we can run multiple commands within the lock.
test/run.sh: Kill subprocesses when test exits

Move trap call so that it is actually executed, and kill any
leftover subprocesses so the test can complete.

Also, unmount chroot with -f.
tests/w?-*: Test all de/wm
test/x0-alltargets: WM/DE are now tested in w*
test/w0-common: Use croutoncycle to detect x11 server started
Merge pull request #1205 from drinkcat/x11test

X11 tests for all de/wm