[clang-tidy] modernize-use-using work with multi-argument templates

Summary:
If clang-tidy's modernize-use-using feature finds any commas that are not within parentheses, it won't create a fix. That means it won't change lines like:
  typedef std::pair<int, int> Point;
to
  using Point = std::pair<int, int>;
or even:
  typedef std::map<std::string, Foo> MyMap;
  typedef std::vector<int,MyCustomAllocator<int>> MyVector;

This patch allows the fix to apply to lines with commas if they are within parentheses or angle brackets that were not themselves within parentheses.

Reviewers: alexfh, hokein, aaron.ballman

Patch by: poelmanc

Subscribers: jonathanmeier, cfe-commits

Tags: #clang, #clang-tools-extra

Differential Revision: https://reviews.llvm.org/D67460