A tool to query the host's LLVM target triple.

After a brief search, I didn't find any combination of existing LLVM command-line tools that does this; at least, writing four lines of code was faster than continuing the search. If anybody knows such an incantation that already exists, I'd be happy to use it instead.
Explicitly use host's target triple for .ll->.o.

In order for our handcoded.ll to be portable, we shouldn't specify a target triple in it. This information needs to come from somewhere, so pass it into clang via the '-target' option.
Remove hardcoded target triple from handcoded.ll.
More thorough 'make clean'