Fix focus (ctrl+alt+F) shortcut behaviour

[pietrodn]

Previous behaviour:

• If the terminal is not focused, focus the terminal
• If the terminal is focused, do nothing
• If the terminal is not visible, crash (issue Uncaught TypeError: Cannot read property 'focusTerminal' of null #189)

Current behaviour:

• If the terminal is not focused, focus the terminal
• If the terminal is focused, return focus to last active element
• If the terminal is not visible, do nothing (fix issue Uncaught TypeError: Cannot read property 'focusTerminal' of null #189)

[Smithx10]

Is this going to get merged? It's driving me crazy.

[Fred-Barclay]

@ivankravets It's a good PR. 😄 I've got it in my fork and it's been working great these past weeks.
(Doesn't change #227 though.)

[Smithx10]

@ivankravets thanks a billion!!! How long is the build + release process? :) I'd love to update and being using this!!!!!

[ivankravets]

@Smithx10 Done!

https://github.com/platformio/platformio-atom-ide-terminal/releases/tag/v2.5.1

[Smithx10]

w00h0000 UPDATING!@

[Smithx10]

This isn't working as expected, cmd + alt + f focus's, cmd +alt +f doesn't return to the editor on the mac. :(
Update it is only working with "LeftAlt + cmd + f" . Might be a bug with "RightAlt + cmd +f"

[ivankravets]

Would be thankful if someone improves this PR. We are currently busy with upcoming release of PlatformIO IDE 2.0 and PIO Unified Debugger.

• http://platformio.org/platformio-ide

[Fred-Barclay]

@Smithx10 Do Macs handle RightAlt differently than LeftAlt?

[isaacjwilliams]

@Smithx10 I'm experiencing the same problem! I bound ctrl-; to 'platformio-ide-terminal:focus'. It switches focus to the terminal correctly, but when I invoke it again, it does nothing at all.