Merge branch 'ng/parallel-tests' into ng/master

* ng/parallel-tests:
  [ng] perf: optimize 'am__strip_suffixes' for speed
  [ng] check: memoize some internal vars (avoid useless recalculation)
  [ng] check: per-suffix dependencies for test cases
  [ng] check: few minor simplifications
  [ng] tests: remove overly picky test cases (and fix few typos)
  [ng] check: AM_LAZY_CHECK="yes", not RECHECK_TESTS="", for lazy re-runs
  [ng] check: refactor: split recipes for check-TESTS and recheck
  [ng] check: minor refactoring (prefer make time over recipe time)
  [ng] check: minor refactoring (reorder code)
  [ng] check: refactor (better names for internal vars)
  [ng] check: refactoring to reduce code duplication
  [ng] refactor: get rid of am__EXEEXT (automake conditional and %transform)
  [ng] check: big refactoring with semantic changes in parallel-tests support

diff --cc doc/automake-ng.texi
Simple merge

diff --cc t/parallel-tests-fork-bomb.sh
Simple merge