[Driver] Change UniversalDriver to use TD file.

Easier to add new options such as -version, and easy to parse.

Now displays a help message with -help

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@193301 91177308-0d34-0410-b5e6-96231b3b80d8
Fix Comments.

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@193302 91177308-0d34-0410-b5e6-96231b3b80d8