Rename src/ to libweston/

This clarifies what is supposed to be the libweston code.

v2: screen-share.c is already in compositor/ instead.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-by: Yong Bakos <ybakos@humanoriented.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Quentin Glidic <sardemff7+git@sardemff7.net>
Tested-by: Quentin Glidic <sardemff7+git@sardemff7.net>
Tested-by: Benoit Gschwind <gschwind@gnu-log.net>
Acked-by: Benoit Gschwind <gschwind@gnu-log.net>
[Pekka: rebased]

diff --git a/tests/surface-global-test.c b/tests/surface-global-test.c
index 11b2455..b0a1d1c 100644
--- a/tests/surface-global-test.c
+++ b/tests/surface-global-test.c
@@ -27,7 +27,7 @@
 
 #include <assert.h>
 
-#include "src/compositor.h"
+#include "compositor.h"
 
 static void
 surface_to_from_global(void *data)