Megacommit of dozens of files.

Cleanup of redundant/useless header file inclusion.

ISC style lint, primarily for function declarations and standalone
comments -- ie, those that appear on a line without any code, which
should be written as follows:
   /*
    * This is a comment.
    */

lib/isc/unix/socket.c

@@ -30,11 +30,9 @@
 #include <unistd.h>
 #include <fcntl.h>
 
-#include <isc/assertions.h>
 #include <isc/buffer.h>
 #include <isc/bufferlist.h>
 #include <isc/condition.h>
-#include <isc/error.h>
 #include <isc/list.h>
 #include <isc/log.h>
 #include <isc/mem.h>