Updates cardstacks w/ isis
Wikimedia links in iframe point to mobile sites

Links to wikimedia sites in a wikipedia mobile site will point to the
mobile version of the wikimedia site (Wikipedia usually just gives out
regular links). A new content script overrides these so that the mobile
link is presented.
Adds measurements to find space on page margins
Fixes timeout for selecting text

Double clicking would create two context panes that overlapped.
Merge remote-tracking branch 'origin/dev' into dynamic-pane-location
Revert "Fixes timeout for selecting text"

This reverts commit 43f60423db5509ff021af376e4e0f234b303a098.
Merge remote-tracking branch 'origin/dev' into dynamic-pane-location
Checks if there's space for pane on the right

If there's no space to the right, pane is placed at the bottom
Enforces minimum frame height

Before, if a selected word were close enough to the bottom of the page,
the frame would have a height close to 0