Squashed 'external/devlib/' changes from 3c28c280..20d1eaba

20d1eaba module/cpuidle: Fix incorrect path check
45ee68fd utils/android: Add support for using aapt2
b5246244 utils/android: Update to discover android tools from PATH
bae741dc docs/overview: Fix python2 style print
b717deb8 module/cpuidle: Simplify Cpuidle.__init__
ccde9de2 devlib/AndroidTarget: Update screen state methods to handle doze
c25852b2 utils/android: Allow instantiating an ApkInfo object without a path.
f7b7aaf5 utils/ssh: Do not attempt to push files recursivley and add logging
569e4bd0 LogcatCollector: Learn to pass format to logcat
07cad780 utils/version: dev version bump
21cb10f5 utils/ssh: Add logging to sftp file transfer
d2aea077 target/ChromeOsTarget: Update ssh parameter list
d4640535 utils/ssh: Fix typo
cfb28c47 utils/ssh: Allow SSH to use SCP as a file transfer method
b941c6c5 utils/ssh: Move the scp transport method to the SSH base class
ea9f9c87 docs/ssh: Add note about connecting to passwordless machines.
4f103876 utils/ssh: Only attempt loading ssh keys if no password is supplied
a4f92317 collector/perf: Disable pager for perf event list.
3c85738f docs/target: Fix method name
45881b9f utils/android: Expose `connection_attempts` argument to `AdbConnection`
a8ff622f target: Propergate adb_server in all `adb_command`s
fcd2439b LogcatCollector: flush the log before terminating pexpect.spawn()
3709e06b utils/android: LogcatMonitor: put pexpect.spawn() in str mode
7c8573a4 README: Update to include installation notes for `paramiko`
6f1ffee2 platform/arm: Decode IP address directly
7ade1b8b platform/arm: Don't specify "Android" in the debug print.

git-subtree-dir: external/devlib
git-subtree-split: 20d1eabaf049056dd2a5b5fb085aa07495d43a90