Merge branch 'next'
Bugfix: don't focus unmapped container on manage

A window may become unmapped on manage when an assignment command unmaps
the window, such as moving it to the scratchpad or killing it.

This can cause i3 focus to be an unmapped window and different than X
focus which can lead to complications

fixes #1283
Merge branch 'fix-focus-unmapped'
Merge branch 'master' into next
Implement EWMH desktop names

Maintain the _NET_DESKTOP_NAMES property on the root window.

http://standards.freedesktop.org/wm-spec/latest/ar01s03.html#idm140251368131760

> _NET_DESKTOP_NAMES
>
> _NET_DESKTOP_NAMES, UTF8_STRING[]
>
> The names of all virtual desktops. This is a list of NULL-terminated
> strings in UTF-8 encoding [UTF8]. This property MAY be changed by a
> Pager or the Window Manager at any time.
Implement the window::urgent event

The window::urgent event is emitted when a container becomes urgent or
loses its urgent status.
Cross-output focus focus floating exception

Focusing across outputs with `focus [direction]` should focus an
existing floating con when no tiling con exists on the output in
[direction].
Consider motif border for floating geometry

When calculating the geometry of a floating window with motif hints that
specify a border style, take into account that this window will have a
different border style when calculating its position with
floating_enable() when the window becomes managed.

A nice side effect of this is that users can override motif hints with
`new_float` config directives when they are specified other than
`normal`.

fixes #1270
remove unneeded render on unmap

tree_render() will call x_push_changes(), so calling it afterward is not
needed.
remove unneeded render on map request

manage_window() will call tree_render() when appropriate, so pushing
changes to X here is not needed.
Handle WM_CHANGE_STATE requests for iconic state

http://tronche.com/gui/x/icccm/sec-4.html#s-4.1.4

 > IconicState - The client's top-level window is iconic (whatever that
 > means for this window manager). The client can assume that its
 > top-level window is not viewable, its icon_window (if any) will be
 > viewable and, failing that, its icon_pixmap (if any) or its
 > WM_ICON_NAME will be displayed.

For these requests, we just close the window.

fixes #1279
add log messages for the detected DPI

Currently, the DPI is only logged when pango fonts are used, which is
often not the case when people report problems with the DPI detection.
Merge branch 'log-dpi'
Merge branch 'master' into next