Squashed 'external/devlib/' changes from e01a76ef..2e81a72b

2e81a72b ssh: Fix command line echoing
22f2c8b6 acmecape: Fix buffer_size use with pipes.quote()
c2db6c17 Add adb_server option in android background connection

git-subtree-dir: external/devlib
git-subtree-split: 2e81a72b39053565b94140e83b894e05ae2b8b8f