* maint:
  maint: more adjustments to the new versioning scheme
  aclocal: fix for more-than-once specified directories
  aclocal: just warn if the primary local m4 dir doesn't exist (don't error)
  coverage: expose automake bug#13760
  tests: refactor/enhance tests about make dry-run mode
  maint: describe new versioning and branching scheme, and adjust to it
  cosmetics: fix some "docstring-like" comments in automake

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>