Cleanup and documentation updates:

- Remove shared/str.h where not used.
- Remove shared/debug.h from all files as it has been completely replaced
  by shared/report.h (it will be removed later).
- Add more doxygen comments to shared/* and clients/lcdproc/*.
- Include static functions in doxygen output.

clients/lcdexec/menu.c

@@ -16,7 +16,6 @@
 #include <string.h>
 #include <strings.h>
 
-#include "shared/str.h"
 #include "shared/report.h"
 #include "shared/configfile.h"
 #include "shared/sockets.h"