G-p-m hding while on AC

Hey all,

I just noticed that g-p-m now hides while on AC. I think this is
horrible default, for several reasons.

1. I cannot tell what my battery is doing while I am on AC. Maybe I am
just on AC until my battery is charged and then going elsewhere.

2. More savvy users might think that g-p-m is crashing open AC plugin

3. No other DE or OS does this. While this is not usually an argument,
I think the expectation of least surprise holds here and there is no
compelling argument to break consistency.

Corey