Upgrade to apm 0.96
:memo: Add installing on debian steps
Upgrade to settings-view@0.145
Upgrade to language-xml@0.21
Force scrollbars to be GPU layers when acceleration is enabled

Fixes #3559

For some reason, Chromium 37 is not compositing scrollbars correctly on
secondary monitors in OS X. They’re invisible when the lines layer
extends beneath the scrollbars unless we apply this style.