Bind middle-click to close tab

Closes #832
Change url-handler example to firefox -new-window

Firefox removed the ability to open private windows with a link
Define AI_ADDRCONFIG in inet.h, needed by OpenBSD
Rewrite dns command

- Cross platform
- Doesn't depend on external tools
Fix warnings
Don't select tab while closing with middle-click

Also fix unused warning and ignore shift right click
libsexy: Properly reflect reset attributes in input
Login when /server is used on known hostname

This brings back old behavior where you can /server to another
server in the same network and login with services but now is only
sent when the server is known not every time so more secure.
... and ignore blank network passwords
Update Translations
Fix Turkish translation & update language list
Add Turkish language to preferences

Users of uk, vi, and wa languages will have to manually change their
lang on Windows after this.
Support numeric 908
... Add inbound_sasl_supportedmechs to inbound.h
Add another badge to readme
Tweak 908 syntax
Build system improvements

- Use AM_GLIB_GNU_GLIB and IT_PROG_INTLTOOL
- Use gnome-autogen.sh
- Move language list to own file
- Delete generated config.rpath file
configure.ac: Actually check the CFLAGS and LDFLAGS returned by ExtUtils::Embed before deciding to compile the Perl plugin.

- openSUSE has ExtUtils::Embed, EXTERN.h and perl.so in the base perl package.
- Fedora has ExtUtils::Embed in a separate perl-devel package.
- Mageia has ExtUtils::Embed in the base perl package but EXTERN.h in a separate perl-devel package. Without this package, the compiler complains about the missing header.
- Debian has ExtUtils::Embed and EXTERN.h in the base perl package but perl.so in a separate libperl-dev package. Without this package, gcc compiles successfully but complains at link-time about -lperl (ExtUtils::Embed returns '-lperl' in ldopts but it's not actually installed).

configure.ac already requires ExtUtil::Embed to enable perl. To handle the case of Mageia and Debian, this change uses AC_TRY_LINK to verify that the flags returned by ExtUtils::Embed can actually be used to compile before deciding to enable the perl plugin.
Move acinclude.m4 into m4 dir
Clean up formatting during build