Merge pull request #1212 from hwhw/master

fix item number distinction (plural forms)
Some English improvements in evernote.koplugin
gettext: unescape \n

Fixes the problem that any msgid with \n in it wouldn't show up translated.
Merge pull request #1214 from Frenzie/master

Some English improvements in evernote.koplugin
Merge pull request #1215 from Frenzie/gettext

gettext: unescape \n
refactoring: reuse IconButton for config menu bar
consider also the screen size when scaling by DPI
default autoscale for IconButton
remove hardcoded footer height of reader menu
Merge pull request #1216 from chrox/auto_scale

auto scale icon button especially for screen with high DPI
refactor refresh

Lots of the device-related distinction wandered into
base/ffi/framebuffer_<driver>. This eases the refresh logic in
UI manager, which basically only decides what kind of refresh
to trigger. The device specific configuration in the framebuffer
driver decides how to realize that whish.

screen.lua is gone, in its place is now the framebuffer driver.
The device abstraction decides what framebuffer driver to load.
update base

pulls the needed changes in base for the refresh refactoring
switch from scaleByDPI() to scaleBySize()