Cleanup: reorganize doxygen modules

- Nest compositor pages under the compositor module
- Nest GUI, DNA/RNA & externformats modules under Blender.
- Remove modules from intern which no longer exist.
- Add intern modules (atomic, eigen, glew-mx, libc_compat, locale,
  numaapi, rigidbody, sky, utfconv).
- Use 'intern_' prefix for intern modules since some of the modules
  use generic terms such as locale & atomic.

intern/atomic/atomic_ops.h

@@ -45,7 +45,7 @@
  */
 
 /** \file
- * \ingroup Atomic
+ * \ingroup intern_atomic
  *
  * \brief Provides wrapper around system-specific atomic primitives,
  * and some extensions (faked-atomic operations over float numbers).

intern/atomic/intern/atomic_ops_ext.h

@@ -44,6 +44,10 @@
  * The Original Code is: adapted from jemalloc.
  */
 
+/** \file
+ * \ingroup intern_atomic
+ */
+
 #ifndef __ATOMIC_OPS_EXT_H__
 #define __ATOMIC_OPS_EXT_H__
 

intern/atomic/intern/atomic_ops_msvc.h

@@ -26,6 +26,10 @@
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+/** \file
+ * \ingroup intern_atomic
+ */
+
 #ifndef __ATOMIC_OPS_MSVC_H__
 #define __ATOMIC_OPS_MSVC_H__
 

intern/atomic/intern/atomic_ops_unix.h

@@ -44,6 +44,10 @@
  * The Original Code is: adapted from jemalloc.
  */
 
+/** \file
+ * \ingroup intern_atomic
+ */
+
 #ifndef __ATOMIC_OPS_UNIX_H__
 #define __ATOMIC_OPS_UNIX_H__
 

intern/atomic/intern/atomic_ops_utils.h

@@ -44,6 +44,10 @@
  * The Original Code is: adapted from jemalloc.
  */
 
+/** \file
+ * \ingroup intern_atomic
+ */
+
 #ifndef __ATOMIC_OPS_UTILS_H__
 #define __ATOMIC_OPS_UTILS_H__