Add meson build configuration

Currently the editor will not work if it is not installed.

There is also a caveat about the 'data' directory which is installed
in the bin directory. This may work but does not seem ok because it is
pollution a shared bin directory and the 'data' folder may not be unique
to Lite.

src/renderer.c

@@ -2,7 +2,7 @@
 #include <stdbool.h>
 #include <assert.h>
 #include <math.h>
-#include "lib/stb/stb_truetype.h"
+#include "stb_truetype.h"
 #include "renderer.h"
 
 #define MAX_GLYPHSET 256