my/crc32c: fix compiler diagnostics generated when compiling with -Wmissing-prototypes
my/m4/ax_check_docbook_xslt_min.m4: new
my/m4/ax_prog_xsltproc.m4: new
my/m4/ax_compare_version.m4: new
my/m4/my_check_docbook_ns_xslt_min.m4: new

replace the AX_CHECK_DOCBOOK_XSLT_MIN macro with a MY_CHECK_DOCBOOK_NS_XSLT_MIN
macro that checks for the *namespaced* variant of the DocBook
stylesheets.
my/my_queue: allow queue entries to be arbitrarily sized
my/COPYRIGHT: update copyright years
my/my_queue: use unique symbol names for the memory barrier and mutex implementations

also add a 'struct my_queue_ops' with function pointers for the
different implementations.

this makes it possible to use both the memory barrier and mutex
implementations in a single program, though care must be taken to not
use the 'struct queue *' returned by one implementation with the other
implementation.
Makefile.am: drop -Wl,--as-needed from link editor flags

we don't actually need -Wl,--as-needed since we don't overlink anything,
and apparently OSX's link editor doesn't support it.
Makefile.am: ship LICENSE in the tarball
added wdns_res_to_str(wdns_res res) function
wdns_reverse_name: fixed buffer overflow on invalid input
add warn_unused_result attribute to wdns_reverse_name()
my/zonefile: treat a second SOA as EOF

some ZFAs (e.g., .name) strangely terminate the zone file with a second
SOA, which is technically invalid per IETF and ICANN specs. add a
workaround for these broken zone files by treating a second SOA
encountered in zonefile_read() the same as EOF.

it's not necessary to actually close the FILE object in zonefile_read()
on EOF. this is performed in zonefile_destroy().
my/my_alloc: add my_free macro
my/my_alloc: add MY_ALLOC_WARN_DEPRECATED stuff wrapper functions for calloc, malloc, realloc
my/vector: free -> my_free
my/vector: mark all generated functions with the 'unused' attribute

according to the gcc documentation,

    unused

        This attribute, attached to a function, means that the function
        is meant to be possibly unused. GCC does not produce a warning
        for this function.

this makes sure the functions generated by VECTOR_GENERATE() don't
trigger -Wunused-functions diagnostics when compiled.
my/hex_decode: don't allow use-after-free in error path

in the error case, where the input passed to hex_decode() is invalid,
make sure we don't allow a stray pointer to escape via the 'raw'
parameter-return value. this prevents use-after-free() in callers.
parse_rdata: don't leak 'u' on error return