add userAgent reporting
Added swipe test for 'swipeDown' strategy
Made clearing text faster on Android when there is hint text.

We try several approaches to clear text on Android and only check
for hint text at the end. This can be made faster if we check for
hint text after each clear attempt.
Also modified hasHintText() a bit to make it more reliable.
Fix for sendkeys with Selendroid in CHROMIUM context
Pass '--adb-port=' parameter and fix adb being 'undefined' for rebooting
Merge pull request #3735 from 0x1mason/swipe_test

Swipe test
update appium-adb with getAdbServerPort method
Merge pull request #3785 from paymand/hint_text_detection

Made clearing text faster on Android when there is hint text.
Merge pull request #3622 from Jonahss/userAgent

add userAgent reporting
Fix for getContexts() on Selendroid.
Add warning about localhost in Selenium Node config.

Using `127.0.0.1` for Appium's Selenium Grid node config makes the grid
server unable to contact Appium when located on a different host.
Clarified that in the docs.
Merge pull request #3761 from testobject/master

Fix for Chromedriver not connecting to adb running on non-default port. Take 2
add a retry to getting available devices from instruments (fix #3796)
Merge pull request #3786 from emakiej/selendroid_sendkeys

Fix for sendkeys with Selendroid in CHROMIUM context
Merge pull request #3797 from DylanLacey/master

Add warning about localhost in Selenium Node config.
Create Opera device which sets Opera specific capabilities