Merge alloc_re.c to alloc.c

Merged file alloc_re.c with alloc.c, leaving alloc_re.c empty.
Thus removed file alloc_re.c.
Merge stralloc_* files into one stralloc.c.

Merged all stralloc_*.c sources into a single strallo.c file.
It's far better and convenient to find all related/similar
routines into a single file, than having to shuffle between
thousands of tiny files. Thus removed nano files.

Updated Makefile.am to compile one stralloc.c, and remove rest
of the stralloc_*.c files.
Convert ANY queries to use TCP sockets.

Changed `dns_transmit_start' routine to send requests over TCP
sockets when doing `ANY' queries. This helps to mitigate DNS
reflection attacks. Patch from Scott Brynen:
  -> http://marc.info/?l=djbdns&m=135734230220249&w=2