Use @sample keyword
devel/libevent2: Fix typo that blocked building with openSSL

PR:		193006
Reported by:	poyopoyo (puripuri.plala.or.jp)
Fix the build with GCC 4.8.  Coin mixes stdlib.h (the C header) and cstdlib
(the C++ header) quite freely, which results in conflicts and fails with
recent compilers.  Address this via a post-patch substitution to avoid some
70 individual patches.

PR:		192133
Submitted by:	Christoph Moench-Tegeder <cmt@burggraben.net>
Use CONFIGURE_SHELL and MAKE_SHELL to define SHELL and CONFIG_SHELL

PR:		192981
Approved by:	portmgr (antoine)
- Convert to USES=libtool
- This port runs configure using bash so the libtool script it generates
  must also run with bash; set CONFIGURE_SHELL to accomplish this
- Add INSTALL_TARGET=install-strip
- Remove PTHREAD_CFLAGS and PTHREAD_LIBS
- Remove Xorg dependencies