Rename toggleButton to button.

This button's going to be used for connecting as well as toggling, so
the original name doesn't adequately describe the button anymore.
Change button label from Toggle to Connect.
Strings for connecting.
Support for clearing the large label.
Define the UI when disconnected.
Move switcher discovery creation to a method.
Declare a constant for the switcher address.

This is temporary. Later, this will either be a default and/or exposed
through the Preferences window.
Remove the label from the button.

Since we'll be reusing the button for different purposes, start with a
blank label. We'll initialize it along with the rest of the UI.
Disable the button by default.

Typically, the initial state of the UI, as far as the user is
concerned, will be "connecting." In this state, the button should
already be disabled.
Initialize the UI when launched.
Don't set the focus when the application launches.

Button focus should only be set after a successful connection, when
the button is updated.
Focus the button when we disconnect.
UI for a connection in progress.
Handle button presses.
Reorganize connection state code.
Tweak whitespace.
UI for connecting to the switcher.
Use the button's tag to identify its function.
Hard-code the actual switcher IP address.
Trigger button based on tag.