Update autoconf macros from autoconf-archive 2012.09.08

cfea4ee ax_append_flag: Split file into one macro per file
5f9f40b Use one implementation for C/C++ in ax_cflags_*.m4
48a6e62 ax_cflags_*: Use AX_APPEND_FLAG macro
dc74e8f Updated serial numbers, and re-formatted the macro to be consistent with the rest of the archive.
7d5e931 AC_REQUIRE AX_APPEND_FLAG when appropriate.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Update autoconf macros from pkg-config 0.28

5fc77a9 Add autoconf macros to help packagers install .pc files
5b463c9 Include PKG_CHECK_VAR macro for reading variables in .pc files

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
filterproc.c: Sever owl.h dependency

This fixes ‘make zcrypt’, which currently has no dependency on
owl_prototypes.h listed in Makefile.am.  (We could instead add one,
but that would be just as pointless.)

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Fix perlglue.c dependency on typemap

This was broken by commit 5b3763885bc567edfd96acbeca2b7115b6c17e19.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Clean more files in ‘make clean’

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Uninstall more files in ‘make uninstall’

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Distribute more files in ‘make dist’

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Remove redundant -I$(top_srcdir) from AM_CPPFLAGS

Automake already does this.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Include generated headers with #include <>

http://www.gnu.org/software/autoconf/manual/html_node/Configuration-Headers.html
“With the appropriate -I option, you can use ‘#include <config.h>’.
Actually, it's a good habit to use it, because in the rare case when
the source directory contains another config.h, the build directory
should be searched first.”

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Allow building in a separate build directory

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Generate the barnowl and tester wrapper scripts at build time

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Allow running barnowl within a separate build directory

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Allow testing in a separate build directory

Now we pass ‘make distcheck’.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Don’t distribute generated sources

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Remove pointless ZFreeNotice

It's only meant to be called on a ZNotice_t that was filled in by a libzephyr
call documented to require a ZFreeNotice. This one was filled in manually. (It
happens to not do anything because it calls free on a NULL pointer).