Revert "Turn off extern templates for most uses."

Turning off explicit template instantiation leads to a pretty
significant build time and code size cost. We're better off dealing
with ABI incompatibility issues that come up in a less heavy handed
way.

This reverts commit r189610.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@215740 91177308-0d34-0410-b5e6-96231b3b80d8
Get testsuite running on FreeBSD.

Add initial support for using LIT to run the tests on FreeBSD. 
More work may need to be done to add support for FreeBSD but this is a
good initial step.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@215742 91177308-0d34-0410-b5e6-96231b3b80d8
Revert get testsuite running on FreeBSD.

There is a similar patch up for review. I'll submit my changes via that.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@215750 91177308-0d34-0410-b5e6-96231b3b80d8