Improve page/page_class
Update docs
Update readme.md
Restore strings.xml support on Android
Update Android common/device
Update android/helper.rb
Fix page on iOS
Change current_context= to set_context.

current_context= would only work with self, eg `self.current_context=`,
which makes it stand out in the API.

It also was sending the wrong parameters, changed from sending :context
to :name
Merge pull request #184 from DylanLacey/master

Change current_context= to set_current_context.
Pass element reference, not element, when calling tap
Update app_strings to take optional language arg
Rename press_for_duration to long_press
Rename s_text to text. Remove e_* methods
Format all .rb files
Update tests
Enable page 'static'
Add migration doc
Merge pull request #189 from appium/update_api

Update api
Release 2.0.0
Update release notes