[elpa] externals/async updated (886be4600a -> 20f7757c08)

[ELPA Syncer]

elpasync pushed a change to branch externals/async.

      from  886be4600a Bind package-pinned-packages in children
       new  230b53606f Update commentary in async-package
       new  d08a41295b No need to call package-initialize which is costly
       new  2276bccd62 Only load the new or upgraded packages
       new  93957f5b0f Refresh package-alist in call-back
       new  20f7757c08 Update README


Summary of changes:
 README.md        |  7 +++++++
 async-package.el | 57 ++++++++++++++++++++++++++++++--------------------------
 2 files changed, 38 insertions(+), 26 deletions(-)