Catch attempts to fetch information about non-activated pcap_t's.

The link-layer header type, and list of supported link-layer header
types, aren't set until the pcap_t is activated; return an error for
attempts to fetch them for a non-activated handle.
Just return PCAP_ERROR_NOT_ACTIVATED for some calls.

Return PCAP_ERROR_NOT_ACTIVATED, not PCAP_ERROR (-1), for calls to
pcap_datalink(), pcap_datalink_ext(), and pcap_list_datalinks() if
called on a non-activated pcap_t.  Pre-pcap_create() code will never see
PCAP_ERROR_NOT_ACTIVATED, and code using pcap_create() will either not
see it (if it's correct) or is already getting bogus results (if it's
not correct).

Document that while we're at it.
Add more "not activated" checks.

Add a missing semicolon from the previous checkin, and change some
return values to the standard style (enclosing the return value in
parentheses), while we're at it.
fix typo on manpage install
Sort generated man pages by name in various lists.

Also, re-generate the configure scripts.
Add the generated time stamp precision API man pages to the .gitignore list.
Fix for bluetooth adapters not showing up

when they are added to top of the list of devices
Merge pull request #322 from oxplot/bt-fix

Fix bt_findalldevs() to correctly add devices to the devices list.
More findalldevs fixes.
Fix fat builds on pre-Leopard and post-Lion versions of OS X.

Prior to Tiger, only 32-bit PowerPC was supported, so don't do fat
builds.  For 10.4 through 10.4.3, only 32-bit and 64-bit PPC were
supported; for 10.4.4 through 10.4.6, 32-bit x86 was also supported; for
all later versions of Tiger, 32-bit and 64-bit x86 were also supported.

For everything after Snow Leopard, not just for Lion, only 32-bit and
64-bit x86 are supported; don't just check for Lion, assume anything for
which we don't have specific cases is like that (unless and until Apple
drops support for 32-bit x86 applications).
Hammer into users' heads the idea that they must use pcap_datalink().

Note for pcap_loop()/pcap_dispatch(), and for
pcap_next()/pcap_next_ex(), that in order to interpret the packets you
have to know the link-layer header type for the pcap_t, as returned by
pcap_datalink().

Note in all the places we discuss the value returned by pcap_datalink()
that the program *MUST NOT ASSUME* that it will return a particular
value, and specifically note that the Linux "any" device has a
pcap_datalink() value of DLT_LINUX_SLL even if all the network
interfaces on the system happen to have some other link-layer header
type.
Added TPACKET_V3 support.
Clean up handling of -g and -O flags.

AC_PROG_CC adds -g and -O2 to CFLAGS if you're using GCC; don't bother
adding either of them, or -O, ourselves if we're using GCC.

Add -O for all non-GCC compilers.
Note that clang, for example, is considered "gcc" by autoconf.
We require autoconf 2.61 in configure.in; that suffices.

Don't say "we require 2.50" in various macros.
Update/fix comments.
We no longer use the GCC version, so don't fetch it.
We no longer use the GCC version, so don't fetch it.

Fix some indentation while we're at it.
Don't change the ABI on IRIX depending on .devel.

I'm not sure why we were doing that; if somebody has a good reason to
continue doing it, please let us know what it is.

Also, expand some comments.
remove stray file and update README

.gitignore supercedes .cvsignore, CVS is no more available and LBL URL
has changed.