[ANN] --disable-orcus

[Kohei Yoshida]

You can now set

--disable-orcus

at configure script to disable building the orcus library.  In case you
have difficulty building liborcus and can't find any solution at all,
you now have a solution.

Orcus is now disabled by default on Cygwin, OS X, and iOS and Android
build.  Those who need functionality provided by orcus can always
re-enable it by setting --enable-orcus to the configure script.

Enjoy!

Kohei