Add hotkey 'list' support to send concurrent keycodes

[dearmash]

To better support multiple key macros in a row.

Rather than needing to send +key.a, +key.b, -key.a, -key.b, +key.1, +key.2, etc. specifying up and down for each, you can define the chords more simply:

[[key.a, key.b], [key.1, key.2]]

The macro definition is simpler, and less error prone (see win-edge.py, was pressing control and releasing command).

Also shorthands multiple presses in a row:

[[Keycode.ENTER], [Keycode.ENTER], [Keycode.ENTER]] will press and release enter 3x in a row.

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[dearmash]

Another example of how this cleans up things:

[[Keycode.COMMAND, Keycode.SPACE], 'chrome', [Keycode.ENTER], [Keycode.COMMAND, Keycode.T], 'mail.google.com/mail', [Keycode.TAB], [Keycode.ENTER]]

From anywhere on your computer, this macro will switch to chrome, and switch to your existing gmail tab.

command space chrome enter launches spotlight and opens chrome / brings it to the front
new tab just makes sure we're in a blank address bar no matter what
the mail url tab enter will 'click' on the switch to this tab button

[lesamouraipourpre]

Not functionally tested as I don't have a MacroPad.