This augments the STLExtras toolset with a zip iterator and range
adapter. Zip comes in two varieties: `zip`, which will zip to the
shortest of the input ranges, and `zip_first`, which limits its
`begin() == end()` checks to just the first range.
Recommit r284035 after MSVC2013 support has been dropped.
Patch by: Bryant Wong <github.com/bryant>
Differential Revision: https://reviews.llvm.org/D23252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284623 91177308-0d34-0410-b5e6-96231b3b80d8