uix:ActionBar:ActionGroup bind to `on_dismiss` events of the dropdown
Dropdown scroll fix

DropDown will not scroll if you use the scroll wheel, it will be dismissed instead, this will fix that.
typos

Some typos were corrected.
Corrected typos in docstrings and exceptions
Update screenmanager.py
Update screenmanager.py
Merge pull request #1515 from voen/patch-2

docstring typos
Merge pull request #1516 from voen/patch-3

Corrected typos in docstrings and exceptions
bootstrap: don't block even if the logo tree cannot be copied at all (like an OSError on permission)
atlas: add the ability to specify a size with WIDTHxHEIGHT too.
tuio: add support for /tuio/2dblb (CCV 1.5)
Merge branch 'master' of ssh://github.com/kivy/kivy
atlas: remove bad print
Merge pull request #1513 from chozabu/master

Fix for mis-positoining of cursor on mouse/touch in multi-line text input
ClearColor set to transparent

There's already a window ClearColor to provide some constant background color.  If the screen manager contents are transparent, it makes sense for the screen manager background to be transparent.
ClearColor back to (0, 0, 0, 1) until we know more

See discussion in ae64000280eedd0f75d39578631c6c298ca10c62
Merge pull request #1512 from kivy/drop_down_escape

uix:DropDown escape dismisses the dropdown
Update dropdown.py
Merge pull request #1526 from voen/patch-1

Dropdown scroll fix
doc: revisions to uix/floatlayout.py