Add testcase for EWMH desktop names

Test that the EWMH specified property _NET_DESKTOP_NAMES is updated
properly on the root window. We interpret this as a list of the open
workspace names.

This test is for this commit:

Implement EWMH desktop names

a9c094b7313b48491c182a5da1194a0bb06747aa
Add link to git repository in hacking docs
tests: include error message when unable to create a FIFO

I have seen this message once or twice, but since the actual error
message was not included, I cannot definitely say what’s going on.

I think it might be a race condition where the file with the specified
tmpname() already exists, but let’s be sure before we attempt to fix it.
Add testcase for EWMH desktop viewport

Test that the EWMH specified property _NET_DESKTOP_VIEWPORT is updated
properly on the root window. We interpret this as a list of x/y
coordinate pairs for the upper left corner of the respective outputs of
the workspaces.

This test is for this commit:

feature: implement ewmh desktop viewport property

4205973135f28a0ab0e25a63dbc8c6fff0d3539e
bugfix: default floating border regression

Fixes a bug where a normal floating default border is not applied when
the default tiling border is set to a pixel value.

This bug was introduced in this commit:

43b447855df095c56e860117d53acd0dd09ac42b

Consider motif border for floating geometry

Fixes a comment that claimed default floating border could override
motif hints, which was never the case.

fixes #1305
Handle EWMH requests to change current desktop

This request is used by pagers and bars to change the current
desktop likely as a result of some user action. We interpret this as
a request to focus the given workspace.

for more information see:

http://standards.freedesktop.org/wm-spec/latest/ar01s03.html#idm140251368135008
i3bar: implement custom mouse wheel commands

Users can specify a command to run when a button was pressed on i3bar to
override the default behavior. Currently only the mouse wheel buttons
are supported. This is useful for disabling the scroll wheel action or
running scripts that implement custom behavior for these buttons.

Example:

bar {
    wheel_up_cmd nop
    wheel_down_cmd exec ~/.i3/scripts/custom_wheel_down
}

fixes #1104