Properly fix doxygen out-of-tree build process:

- move Doxyfile to Doxyfile.in: type 'make Doxyfile' to recreate it
- create Doxyfile from Doxyfile.in with make rule:
  - use sed substitution of $(srcdir) to location directories
- delete all doxygen created files with 'make distclean'
- include all required files (including logger.pl) in distribution


git-svn-id: svn://svn.berlios.de/openocd/trunk@1901 b42882b7-edfa-0310-969c-e2dbd0fdcd60