Merge branch 'js/userdiff-cc'

Improves the pattern to match the hunk-header for C/C++.

* js/userdiff-cc:
  userdiff: have 'cpp' hunk header pattern catch more C++ anchor points
  t4018: test cases showing that the cpp pattern misses many anchor points
  t4018: test cases for the built-in cpp pattern
  t4018: reduce test files for pattern compilation tests
  t4018: convert custom pattern test to the new infrastructure
  t4018: convert java pattern test to the new infrastructure
  t4018: convert perl pattern tests to the new infrastructure
  t4018: an infrastructure to test hunk headers
  userdiff: support unsigned and long long suffixes of integer constants
  userdiff: support C++ ->* and .* operators in the word regexp