Support for FreeBSD 10.x boss/ops.
The biggest changes were related to 10.0's replacing gcc with clang and the switch to a new package system. The former required various fixes to Makefiles that hardwired "gcc" and also missing prototypes in source files that clang is particularly obnoxious about. There was also accomodating the normal evolution of the ports tree. New variables were needed in many of the Makefiles for this. Hopefully, all the changes I made are backward compatible, but I don't actually care that much since I hope to never, ever have to remake those older packages! A new emulab version of the m2crypto port was needed to reflect that m2crypto is no longer installed as an .egg file. Casualties: * Emulab assign. As of this commit, assign does not build with clang. It will build, but immediately core dumps if built with a gcc port (gcc46 below). THIS NEEDS TO BE FIXED! * Emulab nsverify. This requires building a pure ns-2.34, which is old and does not compile with clang. Yo...